-Removed-If you go to send feedback (at the bottom of every page) you can send details of any new payment method you wish to use.
I had to do this when my current card expired and was replaced with a new number.
On your home page it'll show the date you first subsribed.
Your subs will renew every 12 months on that date so an e mail is not really necessary.
2 edits
Under MyHome > MySubscription you can make changes to your present credit card or other payment method, up to a point.
"repeat every year unless cancelled" is a common practice on the internet, and most sites don't offer a direct "this time only" option, in my experience. They just give you a cancellation facility.