According to the failed run with verbose logging here https://solutions.qa.canonical.com/testruns/312e80e0-b17a-466d-be30-e03788fbfd6c 

we are still consuming the Postgres notifications concurrently
 
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update e2abeef3-46e1-4d89-8725-6177713b4181] start processing message DELETE silo2.lab0.solutionsqa landscapeamqp-3-4 A 10.246.64.192
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update 3ef5ea26-48c6-460a-a765-4b01945b2321] start processing message DELETE silo2.lab0.solutionsqa ubuntu A 10.246.64.192
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update d606a8ad-6288-4b3c-af21-5cff388a9dbd] start processing message INSERT silo2.lab0.solutionsqa landscapeamqp-3-4 A 0 10.246.64.192
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update 6c557e22-b621-4031-baf1-d77136f3e94e] start processing message 
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update 3ef5ea26-48c6-460a-a765-4b01945b2321] _dns_requires_full_reload = False, need_reload = False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update 3ef5ea26-48c6-460a-a765-4b01945b2321] requires full reload False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update 3ef5ea26-48c6-460a-a765-4b01945b2321] dns update is NOT in progress. The updates are [] and the new updates are [DynamicDNSUpdate(operation='DELETE', name='ubuntu.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone=None, ttl=None, subnet=None, answer='10.246.64.192', ip=None)]
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update e2abeef3-46e1-4d89-8725-6177713b4181] _dns_requires_full_reload = False, need_reload = False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update e2abeef3-46e1-4d89-8725-6177713b4181] requires full reload False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update e2abeef3-46e1-4d89-8725-6177713b4181] dns update is NOT in progress. The updates are [DynamicDNSUpdate(operation='DELETE', name='ubuntu.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone=None, ttl=None, subnet=None, answer='10.246.64.192', ip=None)] and the new updates are [DynamicDNSUpdate(operation='DELETE', name='landscapeamqp-3-4.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone=None, ttl=None, subnet=None, answer='10.246.64.192', ip=None)]
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update d606a8ad-6288-4b3c-af21-5cff388a9dbd] _dns_requires_full_reload = False, need_reload = False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update d606a8ad-6288-4b3c-af21-5cff388a9dbd] requires full reload False
2023-12-07 20:03:26 maasserver.region_controller: [info] [Dynamic update d606a8ad-6288-4b3c-af21-5cff388a9dbd] dns update is NOT in progress. The updates are [DynamicDNSUpdate(operation='DELETE', name='ubuntu.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone=None, ttl=None, subnet=None, answer='10.246.64.192', ip=None), DynamicDNSUpdate(operation='DELETE', name='landscapeamqp-3-4.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone=None, ttl=None, subnet=None, answer='10.246.64.192', ip=None)] and the new updates are [DynamicDNSUpdate(operation='INSERT', name='landscapeamqp-3-4.silo2.lab0.solutionsqa', zone='silo2.lab0.solutionsqa', rectype='A', rev_zone='64.246.10.in-addr.arpa', ttl=30, subnet=None, answer='10.246.64.192', ip=None)]