I am vaguely speechless about this and very disappointed in both BA and BS.

Personally speaking, I'm not sure there's much point in emailing as I'll simply get a cut/paste response, but I hope that at the very least, either company will respond substantively to this second clear and unacceptable failing.

What would help, would be for them to publish an auditable action plan describing what systems and processes they are putting in place to ensure that this never happens again.

I'm not holding my breath.