"The breach affected a limited number of customer records..."
Yes, limited. All of them except one, the CEO Paul David Pester (PDP) because he got his money out early.
This well-publicized mess undoubtedly has led to the hackers pouncing on TSB with everything they have because they know no one is going to notice.
Well, not everything they have. No need to do a Denial of Service attack because that one was self-inflicted. As is the Distributed part, their customers making things even slower.
Or perhaps it's as simple as their upgrade has them running on PDP-11's? Or perhaps a pester has gotten into the code?