Hello Mike,
Unfortunately, when you perform an in-place upgrade from Windows Server 2012 R2 to Windows Server 2019, the Key Management Service (KMS) activation data does not persist through the upgrade process. This means that after the upgrade, the KMS host will need to reinitialize its licensing counters, and the counts will start over at zero. The KMS service needs to start the accumulation of activation requests again.
Best Regards,
Hania Lian
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