SEP 14 Upgrade and Replication

Hello everyone. We have two sites in different geographical locations and are configured as replication partners. Below are the details

Site 1:- SEPM 12.1.4 with SQL backend

Site 2:- SEPM 12.1.4 with embedded database 

Now we intend to do the upgrade to version 14. Prior to performing the upgrade do we have to break the replication and then perform the upgrade. Or when performing the upgrade on site 1 we simply need to stop the SEPM service on site 2 and vice versa when doing the upgrade on site 2?

Thanks