The Xcode 15.4 GA image has been released for Apple Silicon resource classes and can be selected as follows:
macos:
xcode: 15.4.0
Xcode 15.4 Release Notes | Apple Developer Documentation
What’s New
Software
Xcode 15.3 → 15.4
Ruby 3.2.2 → 3.2.3
Python 3.12.1 → 3.12.2
Pip 23.2.1 → 24.0
NodeJS 20.11.1 → 20.12.2
Runtimes
iOS 17.4 → 17.5
tvOS 17.4 → 17.5
watchOS 10.4 → 10.5
visionOS 1.1 → 1.2
VM Image Info
Xcode 15.4 Build 15F31d is installed at /Applications/Xcode-15.4.app
The full manifest of installed software can be found here
For assistance, please create new threads in the Mobile section of the forum (Mobile - CircleCI Discuss ) for community support.