You can check for the device ID in the macOS beta releases, but device IDs for unreleased GPUs will make it into Windows & Linux drivers before macOS. So that's a good place to check for upcoming GPUs such as the W7900.Why checking windows drivers, if it would make more sense, to check the amd drivers on macOS.
Parts of the Navi 31 drivers can be found in the macOS drivers since 2 years...