Hello!! I am copying the answer and posting here in case comments don't get the same visibility. I believe this is the bug number: FB15939005. One thing I forgot to add in the post but I added to the bug is, the Enterprise Key is much smaller than the Developer key, something like half the characters between ---begin key--- and ---end key---. Please let me know if I can be of more support or if I missed something. Thanks again for the help.

I followed this other documentation: https://developer.apple.com/documentation/enterpriseprogramapi/generating-tokens-for-api-requests and generated a JWT token manually. With it, I could curl -v -H 'Authorization: Bearer ' "https://api.enterprise.developer.apple.com/v1/certificates" with success, but for https://appstoreconnect.apple.com/notary/v2/submissions? it fails with 401. Failed for both keys, Developer and Admin access. I also tried changing "aud": from apple-developer-enterprise-v1 to appstoreconnect-v1, just for the sake of trying.

One branch it is working, other is failing on: "Export archive for development, ad-hoc & app-store distribution". The weird part is that the branch that is working was recently rebased on the one failing.

The builds are running again!

Yeah, last Friday I could get some green builds, but then got to the same issue you are facing, "pending requests" forever...

Since yesterday, I am seeing the first one consistently. The message 'An internal error occurred while this artifact was being saved' is showing up in the logs.