Apple watch activation hassle

I didn’t get a new iPhone, still on 15, but I did get a new cellular Apple Watch 10 to replace my older cellular 9. Everything went fine in terms of setting up the watch and its contents, but the new watch would not activate on cellular. It took a 2 hour call with Verizon, and a very nice tech, to get the cellular activated. He advised me never to try and activate a cellular watch for the first four or five days after it comes out. This type of problem is typical for watch activations, he said, for the first few days after the new watch comes out (I tried to activate it on the first day of release).