It was an accident - it's been explained on the ASA site.
But basically someone forgot that the database for the BBS had already been moved to the new server. When the old server developed problems over the weekend he tried to move the backups from it to the new server. Unfortunatly he forgot there was live data on the new server and copied the old out of date data from the old server on top of the new data on the new server.
And since he didn't think there was anything live on the new server - he didn't follow protocol and back things up first. Which is why the policy is to ALWAYS back things up even if you don't think they're important.
This was complicated by the fact that we weren't really ready to start moving to the new server yet so regular scheduled backups weren't running on it yet. I thought they had been enabled when we brought the BBS database over. Now that I know they weren't I'm just glad we didn't jump the gun and move membership and other more vital info over to the new server earlier!
It's not a conspiracy....it's a case of human error. Believe me the person responsible is feeling REAL bad about it as I was on the phone with him when he realized what he had done. If you've never been in that situation you have no idea how bad it feels to make a mistake of that magnitude.
(I learned that lesson the hardway with one of my first clients. Nothing humbles you like accidentally overwriting six months of work in a minute...and then finding out that the nighly backups you had been running were on corrupted tapes

)