diff --git a/SAS/TMSS/backend/services/scheduling/test/t_dynamic_scheduling.py b/SAS/TMSS/backend/services/scheduling/test/t_dynamic_scheduling.py
index 9767b76eb5923e4524c5a93ca4f565720a7c4f28..dccdb7423fb7064787ee6b283dcc4c6781fca353 100755
--- a/SAS/TMSS/backend/services/scheduling/test/t_dynamic_scheduling.py
+++ b/SAS/TMSS/backend/services/scheduling/test/t_dynamic_scheduling.py
@@ -3289,6 +3289,14 @@ class TestDynamicScheduling(BaseDynamicSchedulingTestCase):
           }
         }
 
+        # the original spec from https://tmss.lofar.eu/api/scheduling_unit_blueprint/3703/specifications_doc_with_just_the_parameters is not accepted with the new validation
+        # so, proof that the validation works, and then adapt the spec for the rest of the test.
+        with self.assertRaises(RuleValidationException) as context:
+            su_draft = create_scheduling_unit_draft_from_observing_strategy_template(strategy_template, scheduling_set=scheduling_set, specifications_doc_overrides=spec)
+        self.assertTrue(str(context.exception).startswith("time between latest and earliest transit for targets in task"))
+
+        # adapt the spec for the rest of the test.
+        spec['scheduling_constraints_doc']['sky']['transit_offset'] = {"from": -1800, "to": 1800}
         su_draft = create_scheduling_unit_draft_from_observing_strategy_template(strategy_template, scheduling_set=scheduling_set, specifications_doc_overrides=spec)
         su_blueprint = create_scheduling_unit_blueprint_and_tasks_and_subtasks_from_scheduling_unit_draft(su_draft)
 
@@ -3296,7 +3304,7 @@ class TestDynamicScheduling(BaseDynamicSchedulingTestCase):
         # it should find this unit (and thus, in scheduler.do_dynamic_schedule it should get scheduled)
         best_next_schedulable_unit = self.scheduler.find_best_next_schedulable_unit([su_blueprint], datetime(2024, 2, 16), datetime(2024, 2, 17))
         self.assertIsNotNone(best_next_schedulable_unit)
-        self.assertEqual(su_blueprint.id, best_next_schedulable_unit.id)
+        self.assertEqual(su_blueprint.id, best_next_schedulable_unit.scheduling_unit.id)
 
 
     def test_scheduling_blocks_outside_observation_window_TMSS_2298_bugfix(self):