Unfortunately, it's not possible to switch between the payment plan and the one-time payment options due to complications with trying to pro-rate based on what you've already paid. 

The payment plan you signed up with is the one you will need to keep for your full year in the club. Once your year is up, you are never billed again.

You CAN change your credit or debit card for future payments if you chose the quarterly option--simply go to My Account