I'm attempting to upload an iOS 13-ready version of an app for TestFlight distribution. I get the following error with no further explanation:
"App Store Connect Operation Error
An error occurred uploading to the App Store."
The error occurs almost immediately after the start of the upload phase.
I'm running Xcode 11 beta 6 on MacOS 10.14.6.
The only unusual thing that preceeded this was a request to create a new Apple Distribution Certificate, which I let Xcode do.
Any suggestions on how to diagnose the issue?