is it possible to downgrade server version, saving all backup data and client registrations?
I found this:
" Downgrade process (server)
Stop the UrBackup server, restore
C:\Program Files\UrBackupServer\urbackup or
/var/urbackup from a backup before upgrade and then install the previous version over the beta release."
in Server 2.3.1 beta/Client 2.3.0 beta
Maybe this helps.