Moved house recently and found that my energy supplier was British Gas who, despite me giving them accurate start readings, as well as final ones when I left them for a better supplier after 8 days, used estimate readings and more than doubled the final bill. Took an hour on the phone with them this afternoon to try and sort it out, and apparently my new bill will be here "in the next 5-7 working days" despite it being electronic. You wonder how many people dont question it and just pay.