diff --git a/tests/test_calendar.py b/tests/test_calendar.py
index 51380624dd6c03f91d8516bf88436ff7e1c016c8..7e186f63a96ff60c7b9f67c069211812bc903295 100644
--- a/tests/test_calendar.py
+++ b/tests/test_calendar.py
@@ -142,7 +142,8 @@ class CreateRecurringEventsTest(SingleCourseTestMixin,
                 t = evt.time
                 continue
             else:
-                self.assertEqual(evt.time - t, datetime.timedelta(weeks=1))
+                self.assertTrue(evt.time - t <= datetime.timedelta(weeks=1, hours=1))
+                self.assertTrue(evt.time - t >= datetime.timedelta(weeks=1))
                 t = evt.time
 
     def test_post_success_starting_ordinal_not_specified(self):