Review the procedures for upgrading and downgrading Replication Agent.
Warning!
Replication Agent cannot be downgraded after you use any new features. Before you
use any new features, test the new version of Replication Agent at the same
functional level as your previous version of Replication Agent. Only when you
are satisfied with the new version of Replication Agent at this existing
functional level should you finalize the upgrade by using new features. You
should also make a backup copy of an instance of the Replication Agent version
to which you have upgraded before attempting to use any new feature.