AFAIK, Windows 10 registration amounts to generating a hash based on your hardware and storing it online. If you reinstall Windows 10 now and try to register ag

AFAIK, Windows 10 registration amounts to generating a hash based on your hardware and storing it online. If you reinstall Windows 10 now and try to register again (and have not updated the hardware, e.g. replaced the hard drive), the same hash will be generated again and your machine will be recognized as already registered. So there should be no extra license cost involved.