That's a good question. It's theoretically possible, but I've never tried it. I'd have to pay off my iPhone and get it unlocked just to try it, and I really don't want to spend the extra $500 right now.
Go into your phone's Personal Hotspot settings, turn off the hotspot, and turn it back on. I did that earlier and my MacBook Pro started connecting again.
Congrats! Glad to hear you got it! Good thing I didn't order a day 1 phone again. I hate activation nightmares. Yes, when I get my Apple Watch Series 5 I'm going to go for the AppleCare monthly plan as well. It's nice to know we can have our devices covered until discontinuation.