Thanks for posting on our community forums. We can certainly understand your concerns regarding your bill from your previous address not being taken.
What normally happens when you move is any outstanding bills from the previous address get transferred to your new address, this means that you will get a higher than normal first bill at your new address.
If you're happy for me to send you a private message I can look at both your old and new account and give you the exact amount and dates of your payments for you.
Please click on the purple envelope to accept the chat.