diff --git a/cylc/flow/cycling/iso8601.py b/cylc/flow/cycling/iso8601.py
index 3c8bd3955fa..553b63e4b2f 100644
--- a/cylc/flow/cycling/iso8601.py
+++ b/cylc/flow/cycling/iso8601.py
@@ -88,7 +88,9 @@ def from_nonstandard_string(cls, point_string):
 
     def add(self, other):
         """Add an Interval to self."""
-        return ISO8601Point(self._iso_point_add(self.value, other.value))
+        return ISO8601Point(self._iso_point_add(
+            self.value, other.value, CALENDAR.mode
+        ))
 
     def standardise(self):
         """Reformat self.value into a standard representation."""
@@ -106,25 +108,27 @@ def standardise(self):
     def sub(self, other):
         """Subtract a Point or Interval from self."""
         if isinstance(other, ISO8601Point):
-            return ISO8601Interval(
-                self._iso_point_sub_point(self.value, other.value))
-        return ISO8601Point(
-            self._iso_point_sub_interval(self.value, other.value))
+            return ISO8601Interval(self._iso_point_sub_point(
+                self.value, other.value, CALENDAR.mode
+            ))
+        return ISO8601Point(self._iso_point_sub_interval(
+            self.value, other.value, CALENDAR.mode
+        ))
 
     @staticmethod
     @lru_cache(10000)
-    def _iso_point_add(point_string, interval_string):
+    def _iso_point_add(point_string, interval_string, _calendar_mode):
         """Add the parsed point_string to the parsed interval_string."""
         point = point_parse(point_string)
         interval = interval_parse(interval_string)
         return str(point + interval)
 
     def _cmp(self, other: 'ISO8601Point') -> int:
-        return self._iso_point_cmp(self.value, other.value)
+        return self._iso_point_cmp(self.value, other.value, CALENDAR.mode)
 
     @staticmethod
     @lru_cache(10000)
-    def _iso_point_cmp(point_string, other_point_string):
+    def _iso_point_cmp(point_string, other_point_string, _calendar_mode):
         """Compare the parsed point_string to the other one."""
         point = point_parse(point_string)
         other_point = point_parse(other_point_string)
@@ -132,7 +136,7 @@ def _iso_point_cmp(point_string, other_point_string):
 
     @staticmethod
     @lru_cache(10000)
-    def _iso_point_sub_interval(point_string, interval_string):
+    def _iso_point_sub_interval(point_string, interval_string, _calendar_mode):
         """Return the parsed point_string minus the parsed interval_string."""
         point = point_parse(point_string)
         interval = interval_parse(interval_string)
@@ -140,7 +144,7 @@ def _iso_point_sub_interval(point_string, interval_string):
 
     @staticmethod
     @lru_cache(10000)
-    def _iso_point_sub_point(point_string, other_point_string):
+    def _iso_point_sub_point(point_string, other_point_string, _calendar_mode):
         """Return the difference between the two parsed point strings."""
         point = point_parse(point_string)
         other_point = point_parse(other_point_string)
diff --git a/tests/functional/cyclers/21-360_calendar.t b/tests/functional/cyclers/21-360_calendar.t
deleted file mode 100755
index 5f58beef713..00000000000
--- a/tests/functional/cyclers/21-360_calendar.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test intercycle dependencies.
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/cyclers/21-360_calendar/flow.cylc b/tests/functional/cyclers/21-360_calendar/flow.cylc
deleted file mode 100644
index dd68f0ec60a..00000000000
--- a/tests/functional/cyclers/21-360_calendar/flow.cylc
+++ /dev/null
@@ -1,11 +0,0 @@
-[scheduler]
-    UTC mode = True
-[scheduling]
-    initial cycle point = 20130228T00
-    final cycle point = 20130301T00
-    cycling mode = 360day
-    [[graph]]
-        P1D = foo[-P1D] => foo
-[runtime]
-    [[foo]]
-        script = true
diff --git a/tests/functional/cyclers/21-360_calendar/graph.plain.ref b/tests/functional/cyclers/21-360_calendar/graph.plain.ref
deleted file mode 100644
index 56dba855ee2..00000000000
--- a/tests/functional/cyclers/21-360_calendar/graph.plain.ref
+++ /dev/null
@@ -1,9 +0,0 @@
-edge "20130228T00/foo" "20130229T00/foo"
-edge "20130229T00/foo" "20130230T00/foo"
-edge "20130230T00/foo" "20130301T00/foo"
-graph
-node "20130228T00/foo" "foo\n20130228T00"
-node "20130229T00/foo" "foo\n20130229T00"
-node "20130230T00/foo" "foo\n20130230T00"
-node "20130301T00/foo" "foo\n20130301T00"
-stop
diff --git a/tests/functional/cyclers/21-360_calendar/reference.log b/tests/functional/cyclers/21-360_calendar/reference.log
deleted file mode 100644
index 04bc0b86031..00000000000
--- a/tests/functional/cyclers/21-360_calendar/reference.log
+++ /dev/null
@@ -1,6 +0,0 @@
-Initial point: 20130228T00
-Final point: 20130301T00
-20130228T0000Z/foo -triggered off ['20130227T0000Z/foo']
-20130229T0000Z/foo -triggered off ['20130228T0000Z/foo']
-20130230T0000Z/foo -triggered off ['20130229T0000Z/foo']
-20130301T0000Z/foo -triggered off ['20130230T0000Z/foo']
diff --git a/tests/functional/cyclers/36-icp_fcp_notation.t b/tests/functional/cyclers/36-icp_fcp_notation.t
deleted file mode 100755
index 96d5a35e895..00000000000
--- a/tests/functional/cyclers/36-icp_fcp_notation.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test initial and final cycle point special notation (^, $)
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/cyclers/36-icp_fcp_notation/flow.cylc b/tests/functional/cyclers/36-icp_fcp_notation/flow.cylc
deleted file mode 100644
index d4a18a640a6..00000000000
--- a/tests/functional/cyclers/36-icp_fcp_notation/flow.cylc
+++ /dev/null
@@ -1,15 +0,0 @@
-[scheduler]
-    UTC mode = true
-    allow implicit tasks = True
-[scheduling]
-    initial cycle point = 20160101T00Z
-    final cycle point = 20160102T00Z
-    [[graph]]
-        R1 = foo
-        R1/^ = bar
-        R1/^+PT1H = baz
-        R1/$-PT1H = boo
-        R1/$ = foo[^] & bar[^] & baz[^+PT1H] & boo[^+PT23H] => bot
-[runtime]
-    [[ root ]]
-        script = echo "success"
diff --git a/tests/functional/cyclers/36-icp_fcp_notation/reference.log b/tests/functional/cyclers/36-icp_fcp_notation/reference.log
deleted file mode 100644
index 2d1494da8c1..00000000000
--- a/tests/functional/cyclers/36-icp_fcp_notation/reference.log
+++ /dev/null
@@ -1,7 +0,0 @@
-Initial point: 20160101T0000Z
-Final point: 20160102T0000Z
-20160101T0000Z/foo -triggered off []
-20160101T0000Z/bar -triggered off []
-20160101T0100Z/baz -triggered off []
-20160101T2300Z/boo -triggered off []
-20160102T0000Z/bot -triggered off ['20160101T0000Z/bar', '20160101T0000Z/foo', '20160101T0100Z/baz', '20160101T2300Z/boo']
diff --git a/tests/functional/cyclers/47-icp_fcp_notation.t b/tests/functional/cyclers/47-icp_fcp_notation.t
deleted file mode 100755
index 7f455983e9b..00000000000
--- a/tests/functional/cyclers/47-icp_fcp_notation.t
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test intercycle dependencies.
-. "$(dirname "$0")/test_header"
-#-------------------------------------------------------------------------------
-set_test_number 6
-#-------------------------------------------------------------------------------
-# test initial and final cycle point special notation (^, $)
-TEST_NAME=${TEST_NAME_BASE}
-install_workflow "${TEST_NAME_BASE}" "${TEST_NAME_BASE}"
-TEST_NAME="${TEST_NAME_BASE}-run"
-run_ok "${TEST_NAME}" cylc play "${WORKFLOW_NAME}" --debug --no-detach
-
-TEST_NAME=${TEST_NAME_BASE}-out
-grep_ok "20160101T0000Z/foo" "$HOME/cylc-run/${WORKFLOW_NAME}/log/scheduler/log"
-grep_ok "20160101T0000Z/bar" "$HOME/cylc-run/${WORKFLOW_NAME}/log/scheduler/log"
-grep_ok "20160101T0100Z/baz" "$HOME/cylc-run/${WORKFLOW_NAME}/log/scheduler/log"
-grep_ok "20160101T2300Z/boo" "$HOME/cylc-run/${WORKFLOW_NAME}/log/scheduler/log"
-grep_ok "20160102T0000Z/bot" "$HOME/cylc-run/${WORKFLOW_NAME}/log/scheduler/log"
-#-------------------------------------------------------------------------------
-purge
diff --git a/tests/functional/cyclers/47-icp_fcp_notation/flow.cylc b/tests/functional/cyclers/47-icp_fcp_notation/flow.cylc
deleted file mode 100644
index d4a18a640a6..00000000000
--- a/tests/functional/cyclers/47-icp_fcp_notation/flow.cylc
+++ /dev/null
@@ -1,15 +0,0 @@
-[scheduler]
-    UTC mode = true
-    allow implicit tasks = True
-[scheduling]
-    initial cycle point = 20160101T00Z
-    final cycle point = 20160102T00Z
-    [[graph]]
-        R1 = foo
-        R1/^ = bar
-        R1/^+PT1H = baz
-        R1/$-PT1H = boo
-        R1/$ = foo[^] & bar[^] & baz[^+PT1H] & boo[^+PT23H] => bot
-[runtime]
-    [[ root ]]
-        script = echo "success"
diff --git a/tests/functional/cyclers/49-365_calendar.t b/tests/functional/cyclers/49-365_calendar.t
deleted file mode 100644
index 5f58beef713..00000000000
--- a/tests/functional/cyclers/49-365_calendar.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test intercycle dependencies.
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/cyclers/49-365_calendar/flow.cylc b/tests/functional/cyclers/49-365_calendar/flow.cylc
deleted file mode 100644
index 86073fe8c56..00000000000
--- a/tests/functional/cyclers/49-365_calendar/flow.cylc
+++ /dev/null
@@ -1,11 +0,0 @@
-[scheduler]
-    UTC mode = True
-[scheduling]
-    initial cycle point = 20120228T00
-    final cycle point = 20120301T00
-    cycling mode = 365day
-    [[graph]]
-        P1D = foo[-P1D] => foo
-[runtime]
-    [[foo]]
-        script = true
diff --git a/tests/functional/cyclers/49-365_calendar/graph.plain.ref b/tests/functional/cyclers/49-365_calendar/graph.plain.ref
deleted file mode 100644
index 7f0a0d0706e..00000000000
--- a/tests/functional/cyclers/49-365_calendar/graph.plain.ref
+++ /dev/null
@@ -1,5 +0,0 @@
-edge "20120228T00/foo" "20120330T00/foo"
-graph
-node "20120228T00/foo" "foo\n20120228T00"
-node "20120301T00/foo" "foo\n20120301T00"
-stop
diff --git a/tests/functional/cyclers/49-365_calendar/reference.log b/tests/functional/cyclers/49-365_calendar/reference.log
deleted file mode 100644
index 920807e835e..00000000000
--- a/tests/functional/cyclers/49-365_calendar/reference.log
+++ /dev/null
@@ -1,4 +0,0 @@
-Initial point: 20120228T00
-Final point: 20120301T00
-20120228T0000Z/foo -triggered off ['20120227T0000Z/foo']
-20120301T0000Z/foo -triggered off ['20120228T0000Z/foo']
diff --git a/tests/functional/cyclers/50-366_calendar.t b/tests/functional/cyclers/50-366_calendar.t
deleted file mode 100644
index 5f58beef713..00000000000
--- a/tests/functional/cyclers/50-366_calendar.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test intercycle dependencies.
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/cyclers/50-366_calendar/flow.cylc b/tests/functional/cyclers/50-366_calendar/flow.cylc
deleted file mode 100644
index 1c38cb46777..00000000000
--- a/tests/functional/cyclers/50-366_calendar/flow.cylc
+++ /dev/null
@@ -1,11 +0,0 @@
-[scheduler]
-    UTC mode = True
-[scheduling]
-    initial cycle point = 20130228T00
-    final cycle point = 20130301T00
-    cycling mode = 366day
-    [[graph]]
-        P1D = foo[-P1D] => foo
-[runtime]
-    [[foo]]
-        script = true
diff --git a/tests/functional/cyclers/50-366_calendar/graph.plain.ref b/tests/functional/cyclers/50-366_calendar/graph.plain.ref
deleted file mode 100644
index e49811ab8bf..00000000000
--- a/tests/functional/cyclers/50-366_calendar/graph.plain.ref
+++ /dev/null
@@ -1,7 +0,0 @@
-edge "20130228T00/foo" "20130229T00/foo"
-edge "20130229T00/foo" "20130301T00/foo"
-graph
-node "20130228T00/foo" "foo\n20130228T00"
-node "20130229T00/foo" "foo\n20130229T00"
-node "20130301T00/foo" "foo\n20130301T00"
-stop
diff --git a/tests/functional/cyclers/50-366_calendar/reference.log b/tests/functional/cyclers/50-366_calendar/reference.log
deleted file mode 100644
index a74c1954ed5..00000000000
--- a/tests/functional/cyclers/50-366_calendar/reference.log
+++ /dev/null
@@ -1,5 +0,0 @@
-Initial point: 20130228T00
-Final point: 20130301T00
-20130228T0000Z/foo -triggered off ['20130227T0000Z/foo']
-20130229T0000Z/foo -triggered off ['20130228T0000Z/foo']
-20130301T0000Z/foo -triggered off ['20130229T0000Z/foo']
diff --git a/tests/functional/cyclers/51-recurrence_fmt_1.t b/tests/functional/cyclers/51-recurrence_fmt_1.t
deleted file mode 100644
index 6f90a79e4b5..00000000000
--- a/tests/functional/cyclers/51-recurrence_fmt_1.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test ISO 8601 recurrence format no. 1 with unbounded repetitions
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/cyclers/51-recurrence_fmt_1/flow.cylc b/tests/functional/cyclers/51-recurrence_fmt_1/flow.cylc
deleted file mode 100644
index 8d83a47f1fa..00000000000
--- a/tests/functional/cyclers/51-recurrence_fmt_1/flow.cylc
+++ /dev/null
@@ -1,11 +0,0 @@
-[meta]
-    description = Test ISO 8601 recurrence format 1
-[scheduler]
-    UTC mode = True
-    allow implicit tasks = True
-    cycle point format = CCYY-MM-DD
-[scheduling]
-    initial cycle point = 2010-01-01
-    final cycle point = 2010-01-10
-    [[graph]]
-        R/2010-01-01/2010-01-04 = worf  # 3-day interval
diff --git a/tests/functional/cyclers/51-recurrence_fmt_1/reference.log b/tests/functional/cyclers/51-recurrence_fmt_1/reference.log
deleted file mode 100644
index dda1e323ebd..00000000000
--- a/tests/functional/cyclers/51-recurrence_fmt_1/reference.log
+++ /dev/null
@@ -1,6 +0,0 @@
-Initial point: 2010-01-01
-Final point: 2010-01-12
-2010-01-01/worf -triggered off []
-2010-01-04/worf -triggered off []
-2010-01-07/worf -triggered off []
-2010-01-10/worf -triggered off []
diff --git a/tests/functional/pre-initial/01-basic.t b/tests/functional/pre-initial/01-basic.t
deleted file mode 100644
index b1f413ddace..00000000000
--- a/tests/functional/pre-initial/01-basic.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test simplification of basic conditionals in pre-initial cycling
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/pre-initial/01-basic/flow.cylc b/tests/functional/pre-initial/01-basic/flow.cylc
deleted file mode 100644
index bca29e50d8e..00000000000
--- a/tests/functional/pre-initial/01-basic/flow.cylc
+++ /dev/null
@@ -1,10 +0,0 @@
-[scheduler]
-   UTC mode = True
-[scheduling]
-    initial cycle point = 20100101T00
-    final cycle point = 20100102T00
-    [[graph]]
-        T00 = "a[-P1D] & b => a"
-[runtime]
-    [[a, b]]
-        script = true
diff --git a/tests/functional/pre-initial/01-basic/reference.log b/tests/functional/pre-initial/01-basic/reference.log
deleted file mode 100644
index f8e9ebfb9b9..00000000000
--- a/tests/functional/pre-initial/01-basic/reference.log
+++ /dev/null
@@ -1,6 +0,0 @@
-Initial point: 20100101T0000Z
-Final point: 20100102T0000Z
-20100101T0000Z/b -triggered off []
-20100102T0000Z/b -triggered off []
-20100101T0000Z/a -triggered off ['20091231T0000Z/a', '20100101T0000Z/b']
-20100102T0000Z/a -triggered off ['20100101T0000Z/a', '20100102T0000Z/b']
diff --git a/tests/functional/pre-initial/02-advanced.t b/tests/functional/pre-initial/02-advanced.t
deleted file mode 100644
index e47da93e022..00000000000
--- a/tests/functional/pre-initial/02-advanced.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test nested conditional simplification for pre-initial cycling.
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/pre-initial/02-advanced/flow.cylc b/tests/functional/pre-initial/02-advanced/flow.cylc
deleted file mode 100644
index 3fac2378990..00000000000
--- a/tests/functional/pre-initial/02-advanced/flow.cylc
+++ /dev/null
@@ -1,10 +0,0 @@
-[scheduler]
-   UTC mode = True
-[scheduling]
-    initial cycle point = 20100101T00
-    final cycle point = 20100102T00
-    [[graph]]
-        PT6H = "(a[-PT6H] & b) & c[-PT6H] => a & c"
-[runtime]
-    [[a, b, c]]
-        script = true
diff --git a/tests/functional/pre-initial/02-advanced/reference.log b/tests/functional/pre-initial/02-advanced/reference.log
deleted file mode 100644
index 9592b07f619..00000000000
--- a/tests/functional/pre-initial/02-advanced/reference.log
+++ /dev/null
@@ -1,17 +0,0 @@
-Initial point: 20100101T0000Z
-Final point: 20100102T0000Z
-20100101T0000Z/b -triggered off []
-20100101T0600Z/b -triggered off []
-20100101T0000Z/a -triggered off ['20091231T1800Z/a', '20091231T1800Z/c', '20100101T0000Z/b']
-20100101T0000Z/c -triggered off ['20091231T1800Z/a', '20091231T1800Z/c', '20100101T0000Z/b']
-20100101T1200Z/b -triggered off []
-20100101T0600Z/a -triggered off ['20100101T0000Z/a', '20100101T0000Z/c', '20100101T0600Z/b']
-20100101T0600Z/c -triggered off ['20100101T0000Z/a', '20100101T0000Z/c', '20100101T0600Z/b']
-20100101T1800Z/b -triggered off []
-20100101T1200Z/a -triggered off ['20100101T0600Z/a', '20100101T0600Z/c', '20100101T1200Z/b']
-20100101T1200Z/c -triggered off ['20100101T0600Z/a', '20100101T0600Z/c', '20100101T1200Z/b']
-20100102T0000Z/b -triggered off []
-20100101T1800Z/c -triggered off ['20100101T1200Z/a', '20100101T1200Z/c', '20100101T1800Z/b']
-20100101T1800Z/a -triggered off ['20100101T1200Z/a', '20100101T1200Z/c', '20100101T1800Z/b']
-20100102T0000Z/a -triggered off ['20100101T1800Z/a', '20100101T1800Z/c', '20100102T0000Z/b']
-20100102T0000Z/c -triggered off ['20100101T1800Z/a', '20100101T1800Z/c', '20100102T0000Z/b']
diff --git a/tests/functional/pre-initial/03-drop.t b/tests/functional/pre-initial/03-drop.t
deleted file mode 100644
index 6afb98480a9..00000000000
--- a/tests/functional/pre-initial/03-drop.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test the case of dropping a conditional based on pre-initial cycling
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/pre-initial/03-drop/flow.cylc b/tests/functional/pre-initial/03-drop/flow.cylc
deleted file mode 100644
index f54faf43fdf..00000000000
--- a/tests/functional/pre-initial/03-drop/flow.cylc
+++ /dev/null
@@ -1,10 +0,0 @@
-[scheduler]
-   UTC mode = True
-[scheduling]
-    initial cycle point = 20100101T00
-    final cycle point = 20100102T00
-    [[graph]]
-        PT6H = "a[-PT6H] & b[-PT6H] => a => b"
-[runtime]
-    [[a, b]]
-        script = true
diff --git a/tests/functional/pre-initial/03-drop/reference.log b/tests/functional/pre-initial/03-drop/reference.log
deleted file mode 100644
index cecb29f06a0..00000000000
--- a/tests/functional/pre-initial/03-drop/reference.log
+++ /dev/null
@@ -1,12 +0,0 @@
-Initial point: 20100101T0000Z
-Final point: 20100102T0000Z
-20100101T0000Z/a -triggered off ['20091231T1800Z/a', '20091231T1800Z/b']
-20100101T0000Z/b -triggered off ['20100101T0000Z/a']
-20100101T0600Z/a -triggered off ['20100101T0000Z/a', '20100101T0000Z/b']
-20100101T0600Z/b -triggered off ['20100101T0600Z/a']
-20100101T1200Z/a -triggered off ['20100101T0600Z/a', '20100101T0600Z/b']
-20100101T1200Z/b -triggered off ['20100101T1200Z/a']
-20100101T1800Z/a -triggered off ['20100101T1200Z/a', '20100101T1200Z/b']
-20100101T1800Z/b -triggered off ['20100101T1800Z/a']
-20100102T0000Z/a -triggered off ['20100101T1800Z/a', '20100101T1800Z/b']
-20100102T0000Z/b -triggered off ['20100102T0000Z/a']
diff --git a/tests/functional/pre-initial/06-over-bracketed.t b/tests/functional/pre-initial/06-over-bracketed.t
deleted file mode 100644
index e47da93e022..00000000000
--- a/tests/functional/pre-initial/06-over-bracketed.t
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-# 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#-------------------------------------------------------------------------------
-# Test nested conditional simplification for pre-initial cycling.
-. "$(dirname "$0")/test_header"
-set_test_number 2
-reftest
-exit
diff --git a/tests/functional/pre-initial/06-over-bracketed/flow.cylc b/tests/functional/pre-initial/06-over-bracketed/flow.cylc
deleted file mode 100644
index 64203d91e96..00000000000
--- a/tests/functional/pre-initial/06-over-bracketed/flow.cylc
+++ /dev/null
@@ -1,14 +0,0 @@
-[scheduler]
-    UTC mode = True
-    allow implicit tasks = True
-[scheduling]
-    initial cycle point = 20131225T1200Z
-    final cycle point = 20131225T1200Z
-    [[graph]]
-        T12 = """
-            (a[-P1D]:fail | b[-P1D]:fail | c[-P1D]:fail) => d
-            a & b & c  # Implied by implicit cycling now...
-        """
-[runtime]
-    [[root]]
-        script = true
diff --git a/tests/functional/pre-initial/06-over-bracketed/reference.log b/tests/functional/pre-initial/06-over-bracketed/reference.log
deleted file mode 100644
index 5246592f6c6..00000000000
--- a/tests/functional/pre-initial/06-over-bracketed/reference.log
+++ /dev/null
@@ -1,6 +0,0 @@
-Initial point: 20131225T1200Z
-Final point: 20131225T1200Z
-20131225T1200Z/c -triggered off []
-20131225T1200Z/d -triggered off ['20131224T1200Z/a', '20131224T1200Z/b', '20131224T1200Z/c']
-20131225T1200Z/a -triggered off []
-20131225T1200Z/b -triggered off []
diff --git a/tests/integration/conftest.py b/tests/integration/conftest.py
index 120d64d24ce..ca7ee981bd9 100644
--- a/tests/integration/conftest.py
+++ b/tests/integration/conftest.py
@@ -25,7 +25,6 @@
 
 from cylc.flow.config import WorkflowConfig
 from cylc.flow.option_parsers import Options
-from cylc.flow.network.client import WorkflowRuntimeClient
 from cylc.flow.pathutil import get_cylc_run_dir
 from cylc.flow.rundb import CylcWorkflowDAO
 from cylc.flow.scripts.validate import ValidateOptions
@@ -48,6 +47,7 @@
 )
 
 if TYPE_CHECKING:
+    from cylc.flow.network.client import WorkflowRuntimeClient
     from cylc.flow.scheduler import Scheduler
     from cylc.flow.task_proxy import TaskProxy
 
@@ -326,7 +326,7 @@ def _inner(
 def gql_query():
     """Execute a GraphQL query given a workflow runtime client."""
     async def _gql_query(
-        client: WorkflowRuntimeClient, query_str: str
+        client: 'WorkflowRuntimeClient', query_str: str
     ) -> object:
         ret = await client.async_request(
             'graphql', {
@@ -511,7 +511,7 @@ def reflog():
 
     """
 
-    def _reflog(schd, flow_nums=False):
+    def _reflog(schd: 'Scheduler', flow_nums: bool = False) -> Set[tuple]:
         submit_task_jobs = schd.task_job_mgr.submit_task_jobs
         triggers = set()
 
@@ -613,3 +613,22 @@ def _set_stop(mode=None):
         schd._set_stop = set_stop
 
     return _complete
+
+
+@pytest.fixture
+def reftest(run, reflog, complete):
+    """Fixture that runs a simple reftest.
+
+    Combines the `reflog` and `complete` fixtures.
+    """
+    async def _reftest(
+        schd: 'Scheduler',
+        flow_nums: bool = False,
+    ) -> Set[tuple]:
+        async with run(schd):
+            triggers = reflog(schd, flow_nums)
+            await complete(schd)
+
+        return triggers
+
+    return _reftest
diff --git a/tests/integration/reftests/test_cyclers.py b/tests/integration/reftests/test_cyclers.py
new file mode 100644
index 00000000000..ccc6f718904
--- /dev/null
+++ b/tests/integration/reftests/test_cyclers.py
@@ -0,0 +1,127 @@
+# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
+# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+async def test_360_calendar(flow, scheduler, reftest):
+    """Test 360 day calendar."""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2013-02-28',
+            'final cycle point': '2013-03-01',
+            'cycling mode': '360day',
+            'graph': {
+                'P1D': 'foo[-P1D] => foo'
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20130228T0000Z/foo', ('20130227T0000Z/foo',)),
+        ('20130229T0000Z/foo', ('20130228T0000Z/foo',)),
+        ('20130230T0000Z/foo', ('20130229T0000Z/foo',)),
+        ('20130301T0000Z/foo', ('20130230T0000Z/foo',)),
+    }
+
+
+async def test_365_calendar(flow, scheduler, reftest):
+    """Test 365 day calendar."""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2012-02-28',
+            'final cycle point': '2012-03-01',
+            'cycling mode': '365day',
+            'graph': {
+                'P1D': 'foo[-P1D] => foo'
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20120228T0000Z/foo', ('20120227T0000Z/foo',)),
+        ('20120301T0000Z/foo', ('20120228T0000Z/foo',)),
+    }
+
+
+async def test_366_calendar(flow, scheduler, reftest):
+    """Test 366 day calendar."""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2013-02-28',
+            'final cycle point': '2013-03-01',
+            'cycling mode': '366day',
+            'graph': {
+                'P1D': 'foo[-P1D] => foo'
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20130228T0000Z/foo', ('20130227T0000Z/foo',)),
+        ('20130229T0000Z/foo', ('20130228T0000Z/foo',)),
+        ('20130301T0000Z/foo', ('20130229T0000Z/foo',)),
+    }
+
+
+async def test_icp_fcp_notation(flow, scheduler, reftest):
+    """Test initial and final cycle point special notation (^, $)"""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2016-01-01',
+            'final cycle point': '2016-01-02',
+            'graph': {
+                'R1': 'foo',
+                'R1/^': 'bar',
+                'R1/^+PT1H': 'baz',
+                'R1/$-PT1H': 'boo',
+                'R1/$': 'foo[^] & bar[^] & baz[^+PT1H] & boo[^+PT23H] => bot'
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20160101T0000Z/foo', None),
+        ('20160101T0000Z/bar', None),
+        ('20160101T0100Z/baz', None),
+        ('20160101T2300Z/boo', None),
+        ('20160102T0000Z/bot', ('20160101T0000Z/bar', '20160101T0000Z/foo', '20160101T0100Z/baz', '20160101T2300Z/boo')),
+    }
+
+
+async def test_recurrence_format_1(flow, scheduler, reftest):
+    """Test ISO 8601 recurrence format no. 1 with unbounded repetitions."""
+    wid = flow({
+        'scheduler': {
+            'cycle point format': 'CCYY-MM-DD',
+        },
+        'scheduling': {
+            'initial cycle point': '2010-01-01',
+            'final cycle point': '2010-01-10',
+            'graph': {
+                'R/2010-01-01/2010-01-04': 'worf',  # 3-day interval
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('2010-01-01/worf', None),
+        ('2010-01-04/worf', None),
+        ('2010-01-07/worf', None),
+        ('2010-01-10/worf', None),
+    }
diff --git a/tests/integration/reftests/test_pre_initial.py b/tests/integration/reftests/test_pre_initial.py
new file mode 100644
index 00000000000..d1ed6a6e566
--- /dev/null
+++ b/tests/integration/reftests/test_pre_initial.py
@@ -0,0 +1,118 @@
+# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
+# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+async def test_basic(flow, scheduler, reftest):
+    """Test simplification of basic conditionals in pre-initial cycling"""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2010-01-01',
+            'final cycle point': '2010-01-02',
+            'graph': {
+                'T00': 'a[-P1D] & b => a',
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20100101T0000Z/b', None),
+        ('20100102T0000Z/b', None),
+        ('20100101T0000Z/a', ('20091231T0000Z/a', '20100101T0000Z/b')),
+        ('20100102T0000Z/a', ('20100101T0000Z/a', '20100102T0000Z/b')),
+    }
+
+
+async def test_advanced(flow, scheduler, reftest):
+    """Test nested conditional simplification for pre-initial cycling."""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2010-01-01',
+            'final cycle point': '2010-01-02',
+            'graph': {
+                'PT6H': '(a[-PT6H] & b) & c[-PT6H] => a & c',
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20100101T0000Z/b', None),
+        ('20100101T0600Z/b', None),
+        ('20100101T0000Z/a', ('20091231T1800Z/a', '20091231T1800Z/c', '20100101T0000Z/b')),
+        ('20100101T0000Z/c', ('20091231T1800Z/a', '20091231T1800Z/c', '20100101T0000Z/b')),
+        ('20100101T1200Z/b', None),
+        ('20100101T0600Z/a', ('20100101T0000Z/a', '20100101T0000Z/c', '20100101T0600Z/b')),
+        ('20100101T0600Z/c', ('20100101T0000Z/a', '20100101T0000Z/c', '20100101T0600Z/b')),
+        ('20100101T1800Z/b', None),
+        ('20100101T1200Z/a', ('20100101T0600Z/a', '20100101T0600Z/c', '20100101T1200Z/b')),
+        ('20100101T1200Z/c', ('20100101T0600Z/a', '20100101T0600Z/c', '20100101T1200Z/b')),
+        ('20100102T0000Z/b', None),
+        ('20100101T1800Z/c', ('20100101T1200Z/a', '20100101T1200Z/c', '20100101T1800Z/b')),
+        ('20100101T1800Z/a', ('20100101T1200Z/a', '20100101T1200Z/c', '20100101T1800Z/b')),
+        ('20100102T0000Z/a', ('20100101T1800Z/a', '20100101T1800Z/c', '20100102T0000Z/b')),
+        ('20100102T0000Z/c', ('20100101T1800Z/a', '20100101T1800Z/c', '20100102T0000Z/b')),
+    }
+
+
+async def test_drop(flow, scheduler, reftest):
+    """Test the case of dropping a conditional based on pre-initial cycling"""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2010-01-01',
+            'final cycle point': '2010-01-02',
+            'graph': {
+                'PT6H': 'a[-PT6H] & b[-PT6H] => a => b',
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20100101T0000Z/a', ('20091231T1800Z/a', '20091231T1800Z/b')),
+        ('20100101T0000Z/b', ('20100101T0000Z/a',)),
+        ('20100101T0600Z/a', ('20100101T0000Z/a', '20100101T0000Z/b')),
+        ('20100101T0600Z/b', ('20100101T0600Z/a',)),
+        ('20100101T1200Z/a', ('20100101T0600Z/a', '20100101T0600Z/b')),
+        ('20100101T1200Z/b', ('20100101T1200Z/a',)),
+        ('20100101T1800Z/a', ('20100101T1200Z/a', '20100101T1200Z/b')),
+        ('20100101T1800Z/b', ('20100101T1800Z/a',)),
+        ('20100102T0000Z/a', ('20100101T1800Z/a', '20100101T1800Z/b')),
+        ('20100102T0000Z/b', ('20100102T0000Z/a',)),
+    }
+
+
+async def test_over_bracketed(flow, scheduler, reftest):
+    """Test nested conditional simplification for pre-initial cycling."""
+    wid = flow({
+        'scheduling': {
+            'initial cycle point': '2013-12-25T12:00Z',
+            'final cycle point': '2013-12-25T12:00Z',
+            'graph': {
+                'T12': '''
+                    (a[-P1D]:fail | b[-P1D]:fail | c[-P1D]:fail) => d
+                    a & b & c  # Implied by implicit cycling now...
+                ''',
+            },
+        },
+    })
+    schd = scheduler(wid, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('20131225T1200Z/c', None),
+        ('20131225T1200Z/d', ('20131224T1200Z/a', '20131224T1200Z/b', '20131224T1200Z/c')),
+        ('20131225T1200Z/a', None),
+        ('20131225T1200Z/b', None),
+    }
diff --git a/tests/integration/test_triggering.py b/tests/integration/reftests/test_triggering.py
similarity index 76%
rename from tests/integration/test_triggering.py
rename to tests/integration/reftests/test_triggering.py
index f086d46aa4c..bc1c0df402e 100644
--- a/tests/integration/test_triggering.py
+++ b/tests/integration/reftests/test_triggering.py
@@ -14,21 +14,15 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-async def test_fail(flow, scheduler, run, reflog, complete, validate):
+async def test_fail(flow, scheduler, reftest):
     """Test triggering on :fail"""
     id_ = flow({
-        'scheduler': {
-            'allow implicit tasks': 'true'
-        },
         'scheduling': {
             'graph': {
                 'R1': 'foo:failed => bar'
             }
         },
         'runtime': {
-            'root': {
-                'simulation': {'default run length': 'PT0S'}
-            },
             'foo': {
                 'simulation': {'fail cycle points': 'all'}
             }
@@ -36,11 +30,7 @@ async def test_fail(flow, scheduler, run, reflog, complete, validate):
     })
     schd = scheduler(id_, paused_start=False)
 
-    async with run(schd):
-        triggers = reflog(schd)
-        await complete(schd)
-
-    assert triggers == {
+    assert await reftest(schd) == {
         ('1/foo', None),
         ('1/bar', ('1/foo',)),
     }
diff --git a/tests/integration/test_examples.py b/tests/integration/test_examples.py
index da8b156503d..882d4c10163 100644
--- a/tests/integration/test_examples.py
+++ b/tests/integration/test_examples.py
@@ -240,9 +240,6 @@ async def test_reflog(flow, scheduler, run, reflog, complete):
     they can be compared with the expected outcome.
     """
     id_ = flow({
-        'scheduler': {
-            'allow implicit tasks': 'True',
-        },
         'scheduling': {
             'initial cycle point': '1',
             'final cycle point': '1',
@@ -271,3 +268,25 @@ async def test_reflog(flow, scheduler, run, reflog, complete):
         ('1/x', None),
         ('1/z', ('1/b',)),
     }
+
+
+async def test_reftest(flow, scheduler, reftest):
+    """Test the triggering of tasks.
+
+    This uses the reftest fixture which combines the reflog and
+    complete fixtures. Suitable for use when you just want to do a simple
+    reftest.
+    """
+    id_ = flow({
+        'scheduling': {
+            'graph': {
+                'R1': 'a => b'
+            }
+        }
+    })
+    schd = scheduler(id_, paused_start=False)
+
+    assert await reftest(schd) == {
+        ('1/a', None),
+        ('1/b', ('1/a',)),
+    }
diff --git a/tests/integration/tui/screenshots/test_scheduler_logs.workflow-configuration-file.html b/tests/integration/tui/screenshots/test_scheduler_logs.workflow-configuration-file.html
index 04ebb27ff79..011734bc410 100644
--- a/tests/integration/tui/screenshots/test_scheduler_logs.workflow-configuration-file.html
+++ b/tests/integration/tui/screenshots/test_scheduler_logs.workflow-configuration-file.html
@@ -11,8 +11,8 @@
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">    [[root]]                                                              </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">        [[[simulation]]]                                                  </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">            default run length = PT0S                                     </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
-<span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">                                                                          </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
-<span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">                                                                          </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
+<span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">[scheduler]                                                               </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
+<span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">    allow implicit tasks = True                                           </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">                                                                          </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">                                                                          </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
 <span style="color:#000000;background:#e5e5e5">│</span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">                                                                          </span><span style="color:#000000;background:#e5e5e5">  </span><span style="color:#000000;background:#e5e5e5">│</span>
diff --git a/tests/integration/utils/flow_tools.py b/tests/integration/utils/flow_tools.py
index c26f79c04ac..3b196c0113d 100644
--- a/tests/integration/utils/flow_tools.py
+++ b/tests/integration/utils/flow_tools.py
@@ -73,9 +73,10 @@ def _make_flow(
         .setdefault('simulation', {})
         .setdefault('default run length', 'PT0S')
     )
-    conf = flow_config_str(conf)
+    # allow implicit tasks by default:
+    conf.setdefault('scheduler', {}).setdefault('allow implicit tasks', 'True')
     with open((flow_run_dir / WorkflowFiles.FLOW_FILE), 'w+') as flow_file:
-        flow_file.write(conf)
+        flow_file.write(flow_config_str(conf))
     return id_