Hello Subetans! First, you can now update the payment method on your existing monthly subscription - without having to cancel and start a new one. Simply go to the subscriptions page and click the "Options" button above the "Cancel" button on your active subscription, to go to the new Options page where you can do that. We will be adding to this page in the future :)
Second, we'd like to give a heads up on an upcoming change that will simplify how monthly subscriptions work with Gold Accounts - and, we hope, make them more intuitive to understand. With this update, subscriptions will no longer add 1 month of GA time to your account. Instead, your account will be considered a Gold Account, and get all the perks, while you have an active subscription - and any existing GA time on your account will not be used up while your subscription is active.
For example, let's say you have a Gold Account which expires in 3 weeks, and no subscription. If you start a monthly subscription, you will get to enjoy having a Gold Account for the entire time your subscription is active, and the GA time left on your account will remain paused at 3 weeks. Then, if you stop having a subscription, it will automatically switch back to using up those 3 weeks of Gold Account you had left before you started the subscription.
This update will be released on Monday, February 8th. After the update is released, this change will be in effect immediately for new subscriptions, and will take effect on your next billing cycle for existing active subscriptions.
Finally, we are almost done implementing a way to upgrade or downgrade an existing subscription. without having to cancel and re-subscribe. Please look forward to this feature after the February 8th update if all goes well.