diff --git a/arctic/serialization/numpy_records.py b/arctic/serialization/numpy_records.py
index 76efcd1dd..42ae58422 100644
--- a/arctic/serialization/numpy_records.py
+++ b/arctic/serialization/numpy_records.py
@@ -64,8 +64,11 @@ def _multi_index_to_records(index, empty_index):
     index_tz = []
     for i in index.levels:
         if isinstance(i, DatetimeIndex):
-            tmp = get_timezone(i.tz)
-            index_tz.append(str(tmp) if tmp is not None else None)
+            if i.tz is None:
+                index_tz.append(None)
+            else:
+                tmp = get_timezone(i.tz)
+                index_tz.append(str(tmp) if tmp is not None else None)
         else:
             index_tz.append(None)
 
diff --git a/arctic/store/_version_store_utils.py b/arctic/store/_version_store_utils.py
index 62837be9e..6b4426861 100644
--- a/arctic/store/_version_store_utils.py
+++ b/arctic/store/_version_store_utils.py
@@ -20,9 +20,9 @@ def _split_arrs(array_2d, slices):
     but avoids fancy indexing
     """
     if len(array_2d) == 0:
-        return np.empty(0, dtype=np.object)
+        return np.empty(0, dtype=object)
 
-    rtn = np.empty(len(slices) + 1, dtype=np.object)
+    rtn = np.empty(len(slices) + 1, dtype=object)
     start = 0
     for i, s in enumerate(slices):
         rtn[i] = array_2d[start:s]
diff --git a/arctic/tickstore/tickstore.py b/arctic/tickstore/tickstore.py
index eccca76be..92ac3c9f5 100644
--- a/arctic/tickstore/tickstore.py
+++ b/arctic/tickstore/tickstore.py
@@ -721,9 +721,10 @@ def _pandas_to_bucket(df, symbol, initial_image):
             rtn[COLUMNS][col] = col_data
         rtn[INDEX] = Binary(
             lz4_compressHC(np.concatenate(
-                ([recs[index_name][0].astype('datetime64[ms]').view('uint64')],
+                ([np.array(recs[index_name][0]).astype('datetime64[ms]').view('uint64')],
                  np.diff(
                      recs[index_name].astype('datetime64[ms]').view('uint64')))).tostring()))
+
         return rtn, final_image
 
     @staticmethod
diff --git a/setup.py b/setup.py
index 9137a74f9..64a71f9a0 100644
--- a/setup.py
+++ b/setup.py
@@ -71,42 +71,45 @@ def run_tests(self):
     cmdclass={'test': PyTest},
     setup_requires=["numpy<1.19.0",
                     "setuptools-git",
-                   ],
+                    ],
     install_requires=["decorator",
                       "enum-compat",
                       "mock",
                       "mockextras",
-                      "pandas<1.1.0",
-                      "numpy<1.19.0",
+                      "pandas<=1.5.3",
+                      "numpy<=1.24.2",
                       "pymongo>=3.6.0, <= 3.11.0",
                       "pytz",
                       "tzlocal",
                       "lz4",
-                     ],
+                      ],
     # Note: pytest >= 4.1.0 is not compatible with pytest-cov < 2.6.1.
     # deprecated
-    tests_require=["mock<=2.0.0",
-                   "mockextras",
-                   "pytest",
-                   "pytest-cov",
-                   "pytest-server-fixtures",
-                   "pytest-timeout",
-                   "pytest-xdist<=1.26.1",
-                   "tomli<2; python_version=='3.6'",
-                   "lz4",
-                   "tzlocal<=1.4; python_version<='3.6'"
-                   ],
+    extras_require={
+        "tests": [
+            "mock<=2.0.0",
+            "mockextras",
+            "pytest",
+            "pytest-cov",
+            "pytest-server-fixtures",
+            "pytest-timeout",
+            "pytest-xdist<=1.26.1",
+            "tomli<2; python_version=='3.6'",
+            "lz4",
+            "tzlocal<=1.4; python_version<='3.6'"
+        ],
+    },
     entry_points={'console_scripts': [
-                                        'arctic_init_library = arctic.scripts.arctic_init_library:main',
-                                        'arctic_list_libraries = arctic.scripts.arctic_list_libraries:main',
-                                        'arctic_delete_library = arctic.scripts.arctic_delete_library:main',
-                                        'arctic_enable_sharding = arctic.scripts.arctic_enable_sharding:main',
-                                        'arctic_copy_data = arctic.scripts.arctic_copy_data:main',
-                                        'arctic_create_user = arctic.scripts.arctic_create_user:main',
-                                        'arctic_prune_versions = arctic.scripts.arctic_prune_versions:main',
-                                        'arctic_fsck = arctic.scripts.arctic_fsck:main',
-                                        ]
-                  },
+        'arctic_init_library = arctic.scripts.arctic_init_library:main',
+        'arctic_list_libraries = arctic.scripts.arctic_list_libraries:main',
+        'arctic_delete_library = arctic.scripts.arctic_delete_library:main',
+        'arctic_enable_sharding = arctic.scripts.arctic_enable_sharding:main',
+        'arctic_copy_data = arctic.scripts.arctic_copy_data:main',
+        'arctic_create_user = arctic.scripts.arctic_create_user:main',
+        'arctic_prune_versions = arctic.scripts.arctic_prune_versions:main',
+        'arctic_fsck = arctic.scripts.arctic_fsck:main',
+    ]
+    },
     classifiers=[
         "Development Status :: 4 - Beta",
         "License :: OSI Approved :: GNU Library or Lesser General Public License (LGPL)",
diff --git a/tests/unit/store/test_version_store_utils.py b/tests/unit/store/test_version_store_utils.py
index a8d39a8bb..36ff4f3e5 100644
--- a/tests/unit/store/test_version_store_utils.py
+++ b/tests/unit/store/test_version_store_utils.py
@@ -9,7 +9,7 @@
 
 def test_split_arrs_empty():
     split = _split_arrs(np.empty(0), [])
-    assert np.all(split == np.empty(0, dtype=np.object))
+    assert np.all(split == np.empty(0, dtype=object))
 
 
 def test_split_arrs():
diff --git a/tests/unit/tickstore/test_tickstore.py b/tests/unit/tickstore/test_tickstore.py
index 9df0aab70..a9ca85119 100644
--- a/tests/unit/tickstore/test_tickstore.py
+++ b/tests/unit/tickstore/test_tickstore.py
@@ -40,7 +40,7 @@ def test_mongo_date_range_query():
         call({'sy': 's1', 's': dt(2014, 1, 1, 0, 0, tzinfo=mktz())}, {'e': 1}),
         call({'sy': 's2', 's': dt(2014, 1, 1, 12, 0, tzinfo=mktz())}, {'e': 1})]
 
-    assert query == {'s': {'$gte': dt(2014, 1, 1, 12, 0, tzinfo=mktz()), '$lte': dt(2014, 1, 3, 0, 0, tzinfo=mktz())}}
+    assert query == {'s': {'$gte': dt(2014, 1, 1, 12, 0, tzinfo=mktz("UTC")), '$lte': dt(2014, 1, 3, 0, 0, tzinfo=mktz())}}
 
 
 def test_mongo_date_range_query_asserts():
@@ -92,7 +92,7 @@ def test_tickstore_to_bucket_with_image():
     assert get_coldata(bucket[COLUMNS]['A']) == ([124, 125], [1, 1, 0, 0, 0, 0, 0, 0])
     assert get_coldata(bucket[COLUMNS]['B']) == ([27.2], [0, 1, 0, 0, 0, 0, 0, 0])
     assert get_coldata(bucket[COLUMNS]['D']) == ([0], [1, 0, 0, 0, 0, 0, 0, 0])
-    index = [dt.fromtimestamp(int(i/1000)).replace(tzinfo=mktz(tz)) for i in
+    index = [dt.fromtimestamp(int(i/1000)).astimezone(mktz(tz)).replace(tzinfo=mktz(tz)) for i in
              list(np.cumsum(np.frombuffer(decompress(bucket[INDEX]), dtype='uint64')))]
     assert index == [i['index'] for i in data]
     assert bucket[COLUMNS]['A'][DTYPE] == 'int64'
@@ -157,7 +157,7 @@ def test_tickstore_pandas_to_bucket_image():
     assert np.isnan(values[1])
     assert values[0] == 1 and values[2] == 1
     assert rowmask == [1, 1, 1, 0, 0, 0, 0, 0]
-    index = [dt.fromtimestamp(int(i/1000)).replace(tzinfo=mktz(tz)) for i in
+    index = [dt.fromtimestamp(int(i/1000)).astimezone(mktz(tz)).replace(tzinfo=mktz(tz)) for i in
              list(np.cumsum(np.frombuffer(decompress(bucket[INDEX]), dtype='uint64')))]
     assert index == tick_index
     assert bucket[COLUMNS]['A'][DTYPE] == 'int64'