I would thing one of two things.
1. You've been banned and Dave chose to just delete your name alltogether...
or 2. which is more likely.....
2. You signed up as a member between the time the server was functioning fine, backup was saved, then server went all wonky on everything and was rerolled back to it's last save point. In that case, I would think that anyone, not just you, would have been lost in computer space.