SEPM Embedded to SQL 12x

I recently updated one of our SEPM's to point to a SQL backend. I planned on stopping the services on our other SEPM letting the machines fail over using the MSL and then doing the upgrade on that box and then set replication back up...however, I stopped the services on the server that still has the embedded DB and none of the clients failed over? I'm not sure what the issue there is.

Any ideas?

SEPM and clients are all on 12.1.7