You can downgrade Replication Agent for Microsoft SQL Server from version 15.7.1 to version 15.2 ESD #2 or later.
You may need to downgrade Replication Agent if the upgrade process fails or if replication fails after an upgrade. Replication may fail when new features fail to function as expected or if there are changes to:
DDL and how it is handled by Replication Agent
The format of the origin queue ID (OQID)
The content or structure of the Replication Agent System Database (RASD)
Replication Agent system objects in the primary database
If you are using any new features from Replication Agent 15.7.1, you cannot downgrade. For a list of the new features for Replication Agent 15.7.1, see the Replication Agent New Features.