I wasn't actually asking about moving phones with regards to the lock, but simply the method os setting up the device for a different carrier. The sim swap is by far the most intelligent and straight-forward process on the planet, and it's one of the reasons GSM has just always made sense where every other technology seemed like it was created by a caveman.

John's NAM setup probably answered that question. I suppose locks can come into play as well if you can't reset the NAM on a particular phone.

It will be interesting to see how this is handled on the iPhone, especially a potential GSM/CDMA iPhone. IMO, it doesn't make sense to make a CDMA-only iPhone.