WatchOS downgrade

[Pugilares]

Hello, just got Apple Watch SE (1st gen) brand new. Paired it to my son-s iPhone 7 Plus iOS 15 with no problems.
Then son says he doesn't like it... (he wants Garmin).
So try to pair the watch with my wife-s iPhone 8 Plus iOS 16 and then watchOS upgrade starts to install watchOS 9.0.

The question is - would be this ever possible to erase the watch SE (1st gen) in the future and pair it with iPhone 7 once there was watchOS 9 already installed? Or this is one way ticket and once the wachOS is upgraded to 9 the watch SE (1st gen) would be never again possible do pair witch iPhone 7?

Another question - would it be possible to reject watchOS upgrade and use the watch SE (1st gen) witch iPhone 8 Plus iOS 16 without watchOS 9?

 

[iStorm]

The question is - would be this ever possible to erase the watch SE (1st gen) in the future and pair it with iPhone 7 once there was watchOS 9 already installed? Or this is one way ticket and once the wachOS is upgraded to 9 the watch SE (1st gen) would be never again possible do pair witch iPhone 7?

It's a one-way ticket and won't be able to be paired with the iPhone 7 anymore since it can't run iOS 16.

Another question - would it be possible to reject watchOS upgrade and use the watch SE (1st gen) witch iPhone 8 Plus iOS 16 without watchOS 9?

As far as I know, there's no way to cancel or reject the upgrade. The watch has to be updated to the latest version compatible with the iPhone in order to pair/set it up.