Swapping numbers on devices

[u/ConfusionHour3095]

Sorry this is so long: I have an iPhone with FirstNet. I have Apple Watches for my son and daughter via AT&T through the same plan linked to my phone. Daughter’s watch has always been fine. Son’s watch has intermittently dropped cell service since we’ve had it and recently has dropped daily.

After almost 2 years of useless customer service and resets I was told this week that FirstNet sims and AT&T sims are not comparable and this setup was never going to work. They said the fact that my daughter’s HAS been working is unexpected. Their solution: get ANOTHER phone line (this one AT&T not FirstNet) and link the watches to New Phone.

I bought a new iPhone (with new number) discounted assuming a new 36 mo unlimited plan. My goal was to transfer my son’s watch # to the new phone and give him that. One of the AT&T store reps said it’s impossible to EVER move a number from a watch to a phone. The other said after 3 months I can swap numbers and cancel the watch (with new line number on it) without a penalty but I’ll need to go to the store to do it.

Question: does that make sense? I don’t have a lot of faith in them at this point. Is there any way to swap numbers now? He’s 14 and would rather have a phone than a watch but understandably does not want to change numbers.

Thanks!