We moved in febuarary, we were already BG customers at our flat near bath, moved to truro in cornwall and told BG what we were doing and all the details.
after managing to bill use twice for our last bill at the previous address (sending threatening letters), they now try to take us to court to pay the previous tennents bill for before we moved in!
I am so glad we dumped them and moved to SWEB.. we have called then dozens of times, at our own expense and in our own time - but still we get threatening letters and the customer service drones are apparently unable to stop this happening even after we send them documents proving when we moved.
I really can't believe how fucking incompetant british gas are! not only do they lose all our paperwork - they can't even solve problems internally. So we are going to talk to the press and the ombudsman (in that order, natch) and make sure they take notice.
Never ever trust british gas not to screw you, either deliberately or out of incompetance - get shot of the parasitic outfit as fast as you can before you waste weeks phoning customer service and have a letterbox full of final demands and court threats!!!