Hi eurodancer,
A warm welcome and thanks for posting on our community forums. Sorry for any confusion about your new account number and contract.
As our valued member @jem101 has advised perfectly, when moving you will automatically be created a new account number and contract if you request any changes from your previous package. Your old account number will cease, and your new account number will take precedence at your new address. You will not be paying for two accounts.
Sorry for any confusion this has caused.
Kind regards Jodi.