Re: Why were they locked out?
"That's not a customer service fail, that's an Ops fail. Do not fuck with production, especially other people's production."
That's probably not how the thinking works. Your production - that's what pays the wages. Other people's production - their problem.
The post-mortem should be interesting. If it's just "Our checks had a bug that did such and such instead of that and that. We've fixed it so it won't happen again." that's not very good. The real question is why it was even possible to implement something that would cut off a paying customer without intervention.
It goes back to the comment I made on the Martin Fowler article. It's all very well being a fast mover and fixing your errors so your quality improves quickly; when there's an error it can do substantial damage in the course of discovery.