diff --git a/stock_available_to_promise_release/models/stock_move.py b/stock_available_to_promise_release/models/stock_move.py
index d59d90eb59..4b56993190 100644
--- a/stock_available_to_promise_release/models/stock_move.py
+++ b/stock_available_to_promise_release/models/stock_move.py
@@ -57,8 +57,9 @@ class StockMove(models.Model):
 
     @api.depends("need_release", "rule_id", "rule_id.available_to_promise_defer_pull")
     def _compute_unrelease_allowed(self):
+        user_is_allowed = self.env.user.has_group("stock.group_stock_user")
         for move in self:
-            unrelease_allowed = move._is_unreleaseable()
+            unrelease_allowed = move._is_unreleaseable() and user_is_allowed
             if unrelease_allowed:
                 iterator = move._get_chained_moves_iterator("move_orig_ids")
                 next(iterator)  # skip the current move
@@ -79,10 +80,8 @@ def _is_unreleaseable(self):
         _is_unrelease_allowed_on_origin_moves.
         """
         self.ensure_one()
-        user_is_allowed = self.env.user.has_group("stock.group_stock_user")
         return (
-            user_is_allowed
-            and not self.need_release
+            not self.need_release
             and self.state not in ("done", "cancel")
             and self.picking_type_id.code == "outgoing"
             and self.rule_id.available_to_promise_defer_pull
@@ -787,7 +786,7 @@ def write(self, vals):
     def _is_mergeable(self):
         self.ensure_one()
         return self.state not in ("done", "cancel") and (
-            self.picking_type_id.code != "outgoing" or self.unrelease_allowed
+            not self._is_unreleaseable() or self.unrelease_allowed
         )
 
     def _update_candidate_moves_list(self, candidate_moves):
diff --git a/stock_available_to_promise_release/tests/test_merge_moves.py b/stock_available_to_promise_release/tests/test_merge_moves.py
index 5e08bd8642..9002bf7591 100644
--- a/stock_available_to_promise_release/tests/test_merge_moves.py
+++ b/stock_available_to_promise_release/tests/test_merge_moves.py
@@ -136,3 +136,17 @@ def test_unrelease_at_move_merge_merged(self):
         self.assertEqual(1, len(move))
         self.assertEqual(2 + original_qty_1 + original_qty_2, move.product_uom_qty)
         self.assertEqual(2, move.move_line_ids.qty_done)
+
+    def test_default_merge(self):
+        # check that the merge is still working when the available_to_promise_defer_pull
+        # is False
+        self.wh.delivery_route_id.write(
+            {
+                "available_to_promise_defer_pull": False,
+            }
+        )
+        original_qty = self.shipping1.move_ids.product_uom_qty
+        # run a new procurement for the same product in the shipment 1
+        self._procure(2)
+        self.assertEqual(1, len(self.shipping1.move_ids))
+        self.assertEqual(original_qty + 2, self.shipping1.move_ids.product_uom_qty)