I have the exact same issue for both my iOS apps. Can't add them to external testers in testflight either.

Has anybody gotten this resolved? I see this as a global issue in my developer account too and can't proceed with anything in development :(

I have the same, across all applications. All builds were expired, one during initial review phase. I can't add any build to testflight and only get "There was an error processing your request. Please try again later."