Its the FDIC's job to wargame the "what if" scenario, if things get worse. (Even if there's no evidence in that direction yet).
It would also be mind blowing to me for someone whose job is to handle bank failures to not have a playbook for them. I know that FEMA has a truly impressive library of disaster playbooks in their analogous role.
I have huge respect for the FDIC. I feel they're the perfect example of a government agency that works.