Xcode 14.1 beta 3 on M1! 
To select these Stacks you just have to open your app on bitrise.io,
go to the Workflow tab (Workflow Editor), and on the Stack tab select the Xcode 14.1.x option and your next build will start on the corresponding stack.
*Note: you can now select separate stacks for separate workflows!
Read more at: https://blog.bitrise.io/per-workflow-stack-selection-is-here.
You can find the system reports here:
https://github.com/bitrise-io/bitrise.io/blob/master/system_reports/MACOS/M1/osx-xcode-14.1.x.log
If you’d like to add additional tools to be pre-installed you can find the instructions on GitHub, for both the Linux and for the macOS stacks.
_Information about Stack types & update schedules can be found here: How are the bitrise.io stacks updated and with what frequency? What's the stack deprecation / removal policy?
Happy Building 