I wonder if it's possible to run XCTest via Firebase TestLab on iOS15+ devices/simulators.
I will describe my problem with gcloud command line first:
When running this command in terminal:
gcloud firebase test ios models list
It returns me this devices and os versions list:

And looks like the latest available OS version to run is 14.7 which is available on iPhone8 only.
However, this command:
gcloud firebase test ios versions list
returns me a lot more available versions, including 15.1 as the latest iOS version:

Also, here is the image from Firebase TestLab console, which lists the only available devices just like the first command I mentioned:
... So, is there any way to run my tests on iOS 15 via Firebase TestLab?