upgrade from sdlo 7.6 to 8.0 - rollback options

hi, i'm planning on upgrading my sdlo 7.6 environment (server 2008) to version 8.0

here are my proposed steps:

  enable blackout window

  shutdown dlo server and take snapshot

  perform update from 7.6 to 8.0

  remove blackout window

  test a few machines to ensure 7.6 agent can still backup without upgrading

now my question is, if something was to go wrong, can i revert back to the snapshot without issues?  example, when the blackout window gets removed, and computers start connecting and backing up, and we want to revert back, is this possible without data loss to those computers that just connected and backed up.

thanks.

Phil