foo.diff

diff --git a/server/app_util/tests/data.py b/server/app_util/tests/data.py
index 7d8c03ebd..bd868f291 100644
--- a/server/app_util/tests/data.py
+++ b/server/app_util/tests/data.py
@@ -173,6 +173,11 @@ def utc(dt: datetime):
     return dt.astimezone(pytz.utc)
 
 
+def utc_date(dt: datetime):
+    """Convert a timezone-aware datetime to UTC and then return the date only. Test helper."""
+    return dt.astimezone(pytz.utc).date()
+
+
 def nzt(y: int, m: int, d: int, *args):
     """Create a datetime in Pacific/Auckland timezone, midnight of the given day. Test helper."""
     tz = pytz.timezone("Pacific/Auckland")
diff --git a/server/facilities/tests/views/work_orders/__init__.py b/server/facilities/tests/views/work_orders/__init__.py
index f9badc5b4..acf339591 100644
--- a/server/facilities/tests/views/work_orders/__init__.py
+++ b/server/facilities/tests/views/work_orders/__init__.py
@@ -10,7 +10,14 @@ from rest_framework.test import APIClient
 
 from app_util.collections import find_item
 from app_util.tests.constants import URL_DATE_FORMAT
-from app_util.tests.data import create_test_contact, create_test_work_order, create_test_org_and_property, nzt, utc
+from app_util.tests.data import (
+    create_test_contact,
+    create_test_work_order,
+    create_test_org_and_property,
+    nzt,
+    utc,
+    utc_date,
+)
 from app_util.tests.mixins import GenericModelTestCase
 from app_util.tests.util import assert_contains, assert_some, first_due_date, send_request
 from facilities.models import (
@@ -629,6 +636,65 @@ class WorkOrderTestCase(GenericModelTestCase):
             work_order_date.status,
         )
 
+    def test_simple_update_to_repeating_date_range(self):
+        """
+        If the date (but not the repeat time) of a repeating date is updated, then shift all dates without recreating.
+        """
+
+        task = create_test_work_order(nzt(2022, 1, 31), repeat_time=WorkOrderRepeat.MONTH)
+        wo = task.work_order_content.work_order
+
+        def _single_update(wo, due_date, updates):
+            update_work_order(
+                wo, due_date, updates, disable_notifications=True, edit_type=WorkOrderRepeatEditType.THIS_EVENT
+            )
+
+        _single_update(wo, nzt(2022, 2, 28), {"status": WorkOrderStatus.ON_HOLD})
+        _single_update(wo, nzt(2022, 6, 30), {"status": WorkOrderStatus.SCHEDULED})
+
+        wod_pks = wo.dates.order_by("due_date").values_list("id", flat=True)
+        print(wod_pks)
+
+        # Check updated data - new WODs are created for the updated items, and the values that follow them
+        self.assertListEqual(
+            [
+                (utc(nzt(2022, 1, 31)), utc_date(nzt(2022, 2, 27))),
+                (utc(nzt(2022, 2, 28)), utc_date(nzt(2022, 3, 30))),
+                (utc(nzt(2022, 3, 31)), utc_date(nzt(2022, 6, 29))),
+                (utc(nzt(2022, 6, 30)), utc_date(nzt(2022, 7, 30))),
+                (utc(nzt(2022, 7, 31)), None),
+            ],
+            [(dt.due_date, dt.repeat_end_date) for dt in wo.dates.order_by("due_date")],
+        )
+
+        # From the last of the month to the 15th of the month, updating in the middle of the month
+        update_work_order(
+            wo,
+            nzt(2022, 3, 31),
+            {"due_date": nzt(2022, 3, 15), "start_date": nzt(2022, 2, 16)},
+            disable_notifications=True,
+            edit_type=WorkOrderRepeatEditType.ALL_EVENTS,
+        )
+
+        # Refresh
+        wo = WorkOrder.objects.get(pk=wo.pk)
+
+        # Check updated data - new WODs are created for the updated items, and the values that follow them
+        self.assertListEqual(
+            [
+                (utc(nzt(2022, 1, 15)), utc_date(nzt(2022, 2, 14))),
+                (utc(nzt(2022, 2, 15)), utc_date(nzt(2022, 3, 14))),
+                (utc(nzt(2022, 3, 15)), utc_date(nzt(2022, 6, 14))),
+                (utc(nzt(2022, 6, 15)), utc_date(nzt(2022, 7, 14))),
+                (utc(nzt(2022, 7, 15)), None),
+            ],
+            [(dt.due_date, dt.repeat_end_date) for dt in wo.dates.order_by("due_date")],
+        )
+
+        # The WOD records should have been updated, not recreated
+        updated_pks = wo.dates.order_by("due_date").values_list("id", flat=True)
+        self.assertEqual(wod_pks, updated_pks)
+
     def test_update_content_of_single_repeat_instance(self):
         """Update the content of a single repeat instance ."""
         client, user = self.create_client()