My hub phone will have an area code the same as a normal phone for example the area code for a normal phone in this area is 01455, the hub phone will start 01455 but instead of having a local exchange for example the exchange here is 27 so the first 6 digits of a normal phone will be 0145527 where as with a hub phone it is 88 so that number will be 01455 88 99 00 for example.
The hub phone is a second line but it runs through the BT broadband home hub.
Its a lot cheaper than getting a second line put in.
Matt