Re: Wrong Question!!
Asking "What is your back up plan?" is the wrong question!
I think they're using the term in a different sense than you're interpreting it. "What's your fall-back plan?" would have been less ambiguous. There needs to be a means of carrying on business whilst all the restoration, repair etc. is being undertaken.
The embarrassing thing for the banks is that it might involve customers visiting their local branch. Local? What local branch?