Could you do a cmos reset for the motherboard?
Wouldn't that wipe any key/license?
There just doesn't seem to really be enough documentation for the way this is all going.....
Just a lazy google without a support ticket shows even Microsoft forums do not provide legitimate support answer:
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answers.microsoft.com/en ··· 5c7e68ffWhich leads me to the hardware (motherboard factory reset) is the only way to wipe the key....