After having to wipe my computer, I re-downloaded my standalone LR6, signed out, and signed back in.
Whenever I start LR, I get a Adobe pop up saying that my serial number "is already in use by the maximum allowed computers. You need to deactivate another computer within two days to use this product."
The serial number is correct and pressing the retry option is not successful.
LR does seem to work - but I havent tested this fully to avoid any unwanted surprises.