Correct, except in PBX-talk they are called ports. The port address is related to the card slot on the chassis. For example, the keyset card in slot 4 contains ports 4.1 to 4.16.

Doing a station swap from the admin phone is definitely the easiest way for a non-PBX guy to change extensions. The only real down side is they need to be one-for-one swaps. It can get tricky when moving a bunch of people.

If you don’t know which one is the admin phone, here’s a tip. Leave the handset off-hook on a random phone. After a minute or so, the admin phone will display an off-hook alarm.

If you’re going to maintain this system for a while, I’d buy a punch tool and learn how to use it.