diff --git a/SAS/TMSS/backend/src/tmss/tmssapp/models/specification.py b/SAS/TMSS/backend/src/tmss/tmssapp/models/specification.py
index db045de8f48b8357fac6dc34e5814e681b90a66a..2c90343ecfdfcc1df2e7935f740344be3ae9e763 100644
--- a/SAS/TMSS/backend/src/tmss/tmssapp/models/specification.py
+++ b/SAS/TMSS/backend/src/tmss/tmssapp/models/specification.py
@@ -709,18 +709,6 @@ class TaskTemplate(AbstractSchemaTemplate):
                 if group.get('max_nr_missing', 0) > len(group.get('stations', [])):
                     raise RuleValidationException("station_groups max_nr_missing should be smaller than or equal to the number of stations in the group. max_nr_missing=%s #stations=%s" % (group.get('max_nr_missing', 0), len(group.get('stations', []))))
 
-            # cannot mix lofar1 and lofar2 stations in new(er) templates
-            if self.state.value in (TemplateState.Choices.ACTIVE.value, TemplateState.Choices.DEVELOPMENT.value):
-                from lofar.sas.tmss.tmss.tmssapp.conversions import get_lofar2_stations
-                specified_stations = set(sum([group['stations'] for group in station_groups], []))
-                lofar2_stations = set(get_lofar2_stations())
-                specified_lofar2_stations = specified_stations.intersection(lofar2_stations)
-                if len(specified_lofar2_stations)>0 and specified_lofar2_stations != specified_stations:
-                    raise RuleValidationException("Mixing LOFAR1 and LOFAR2 stations is not supported. TaskTemplate name='%s' version=%s state=%s\n - specified: %s\n - LOFAR2: %s" % (
-                        self.name, self.version, self.state.value,
-                        ','.join(s for s in sorted(specified_stations)),
-                        ','.join(s for s in sorted(lofar2_stations))))
-
             saps = json_doc.get('station_configuration',{}).get('SAPs',[])
             all_subbands = set(sum([sap['subbands'] for sap in saps], []))
             if len(all_subbands) > 488:
diff --git a/SAS/TMSS/backend/test/t_scheduling_units.py b/SAS/TMSS/backend/test/t_scheduling_units.py
index a2ec4c2778eabd5efb526b14c964e1744902d777..5ca8ce092951f2b9097bef929c96f7b4c5d53f99 100644
--- a/SAS/TMSS/backend/test/t_scheduling_units.py
+++ b/SAS/TMSS/backend/test/t_scheduling_units.py
@@ -543,21 +543,22 @@ class SchedulingUnitBlueprintStateTest(unittest.TestCase):
         lofar2_stations = get_lofar2_stations()
         self.assertIn('DE605', lofar2_stations)
 
-        # make sure that the previously blueprinted tasks don't validate any more
-        with self.assertRaises(RuleValidationException):
-            for task in blueprint.task_blueprints.all():
-                task.validate_specifications_doc()
+        # JS 2024-02-26: as per L2SS-1511 combining lofar1&2 stations in one observation IS allowed,
+        # so the RuleValidationException should NOT be raised anymore, and all specs should validate.
+        for task in blueprint.task_blueprints.all():
+            task.validate_specifications_doc()
 
         # start a subtask so that the unit is advance enough to skip rule-based validation on specs read access
         set_subtask_state_following_allowed_transitions(blueprint.subtasks.first(), 'started')
         blueprint.refresh_from_db()
         self.assertEqual(blueprint.status.value, models.SchedulingUnitStatus.Choices.OBSERVING.value)
 
-        # try to create a draft copy, which should fail due to the invalid specs
-        with self.assertRaises(ValidationException):
-            create_scheduling_unit_draft_from_scheduling_unit_blueprint(blueprint)
+        # try to create a draft copy
+        # JS 2024-02-26: as per L2SS-1511 combining lofar1&2 stations in one observation IS allowed,
+        # so the RuleValidationException should NOT be raised anymore, and the copy should be created.
+        create_scheduling_unit_draft_from_scheduling_unit_blueprint(blueprint)
 
-        # try again, but this time remove lofar2 stations when creating the draft so that it can be blueprinted
+        # try again, but this time remove lofar2 stations when creating the draft
         draft_copy = create_scheduling_unit_draft_from_scheduling_unit_blueprint(blueprint, remove_lofar2_stations=True)
         blueprint_from_copy = create_scheduling_unit_blueprint_and_tasks_and_subtasks_from_scheduling_unit_draft(draft_copy)