https://support.microsoft.com/en-us/help/4564903/cumulative-update-14-for-sql-server-2016-sp2
https://download.microsoft.com/download/6/0/6/606B3A2E-0EAE-4DCD-930D-178686370921/SQLServer2016-KB4564903-x64.exe

Долгожданный фикс:
13544150: This improvement includes object level lock optimization on secondary replicas of AlwaysOn Availability Groups and addresses the schema lock contention on secondary replica redo, especially when the number of logical processors is large.
Note This improvement replaces and removes the need for Trace Flag (TF) 1240 from KB4497705.