> setting up in a new region would be complicated for us.
Sounds to me like you've got a few weeks to get this working. Deprioritize all other work, get everyone working on this little DevOps/Infra project. You should've been multi-region from the outset, if not multi-cloud.
When using the public cloud, we do tend to take it all for granted and don't even think about the fact that physical hardware is required for our clusters and that, yes, they can run out.
Anyways, however hard getting another region set up may be, it seems you've no choice but to prioritize that work now. May also want to look into other cloud providers as well, depending on how practical or how overkill going multi-cloud may or may not be for your needs.
I wish you luck.