The very short answer to this is to call us on 0333 202 5000 or email us at [email protected] and an agent will be able to clarify your exact end date for you.
Please note, the date that you signed the contract is NOT your contract end date. The contract was binding when it was signed however it was not "live", when your numbers connected to the network, ie ported over to us or if we connected new connections, this is when your contract became live.