SCOM 2012 R2 UR9 - SQL scripts failing

When running the update_rollup_mom_db.sql script from the UR9 update for SCOM 2012 R2 it would always bomb out after a few minutes with this error:

(1 row(s) affected)
(1 row(s) affected)
Msg 1205, Level 13, State 56, Line 1
Transaction (Process ID 152) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction.
Msg 3727, Level 16, State 0, Line 1
Could not drop constraint. See previous errors.

Out of interest I decided to keep the DAS, Config and Exchange Correlation Engine services running while doing this as I'd never had a problem before. Getting nowhere I then stopped the Correlation Engine and - looking more promising - the script ran for about 20 minutes then bombed out with the same error.

I then stopped the DAS, Config and HealthService services on all management servers as Kevin advises in the article below and the script completed successfully in less than 1 minute. The UR_Datawarehouse.sql script completed successfully too. We did not have to restart any SQL services.

https://blogs.technet.microsoft.com/kevinholman/2016/05/16/ur9-for-scom-2012-r2-step-by-step-2/