If anyone is stuck after upgrading to macOS 27 beta and Xcode 27 beta, this worked for me.
I made the mistake of installing the macOS 27 beta and Xcode 27 beta without keeping a stable environment for App Store submissions. After that, I couldn’t submit updates because Apple requires apps to be built with supported public versions of Xcode.
I didn’t want to restore my Mac or use a second Mac, so I looked for another solution.
Here’s what worked:
I created a private GitHub repository and pushed my project.
I connected the repository to Xcode Cloud in App Store Connect.
I created a workflow in Xcode Cloud.
In the workflow settings, I selected **Xcode 26** and the **macOS Tahoe 26** build environment instead of the beta versions installed on my Mac.
Xcode Cloud built the app on Apple’s servers using those stable versions and submitted it directly to App Store Connect.
Even though my Mac is still running macOS 27 beta and Xcode 27 beta, the build was created with the stable environment in Xcode Cloud, so the submission was accepted.
My app is now **Waiting for Review**.
If you’re in the same situation, this may save you from having to restore your Mac, borrow a second Mac, or wait until the public release of macOS 27.