The reason why this is even a problem in the first place is because of all the piracy. Not piracy, no software protection. It’s a problem that shouldn’t have existed in the first place, but now we all have to bear the pain because of the actions of a few.
There is no perfect solution, unfortunately. I also thought that it would be better for Waves to offer online licenses too, but that doesn’t work for systems without an internet connection. Believe it of not there are plenty of studios that like to keep their systems isolated, so it begins to be a problem. Consider also, what happens if the internet decides to go down for whatever reason.
If you have a valid WUP or subscription you do also get a second license. So one way to approach this type of potential issue is to keep your secondary licenses on a backup drive, just in case of emergency. Of course all emergency systems need to be periodically tested, so I would suggest firing it up once or twice a year to make sure everything is working as expected. Of even just before an important job.
It’s not ideal, but it will get you past problems like this and it will even work if there is sudden internet drop out.