When attempting to add a recent build to an External test group, I am receiving the error:
This build is using a beta version of Xcode and can’t be submitted. Make sure you’re using the latest version of Xcode or the latest seed release found on the releases tab in News and Updates
This build is a macOS app built with Unity, which is then codesigned, packaged with productbuild, and then uploaded with xcrun altool --upload-package.
The version of Xcode being used was released about a week ago.
Xcode Version 15.4 (15F31d), built of an Intel Mac Mini running macOS 14.4.1 (23E224).
I have seen threads in the past about this, but nothing recent. (1,2)