How is this not either a bug in their software/systems or some mistake? Does being "prepared" mean 100% availability/uptime? Even very mission critical systems like the Sabre system that powers many of the world's airlines can't maintain 100% uptime indefinitely.

I think regulators should be much more concerned with integrity than uptime. Losing temporary access to my account balance is bad, but not nearly as bad as the bank showing an incorrect balance.