Migration from Ubuntu 7.10 to Debian 4.0

I have a couple of existing servers that run on Ubuntu 7.10, and I’m trying to come up with a gameplan to migrate them Debian 4.0 with Virtualmin GPL.

Will Ubuntu 8.04 support hit GPL any time soon?

If so, how’s this for a six-step plan:

  1. Upgrade to Ubuntu 8.04
  2. Install Virtualmin GPL
  3. Modify the domains and setup to run under Virtualmin (the time-consuming part)
  4. Backup all the virtual servers
  5. Delete Ubuntu and install Debian and Virtualmin GPL
  6. Restore all the virtual servers

My hope is that would get things switched over with minimal downtime of the things people notice, like Apache, Postfix, and Dovecot. If I had an extra machine, I would simply rebuild the server offline and flip the switch, but I don’t.

Thanks for any thoughts or advice.