Hope you can share what you learnt from this incident and hopefully you'll take a hard look at your processes.
I'd hate to be caught in the same issue, especially that we are already customers, and I'm not sure I'll have as much clout as Nicolas here to get your attention.
It's occurring to me now that while I've successfully ignored twitter for years, I should probably rectify that just so I have somewhere to type my hopes and prayers when this eventually happens to me, and hope for a miracle. It sure seems like the only place they're listened to.
Maybe keeping a twitter (and other social media) account with at least a certain number of follower should be considered a part of a company's security strategy? You'd also need to post something interesting periodically, to keep your follower, so that you have their attention when you need it.