To update, add or remove a credit card on file in your account go to the Shop page and under the drop down next menu to your initials and choose My Wallet:
From there you can add, remove or edit a card on file:
You can also change your credit card before your confirm your purchase as long as you buy the product directly from the online shop first, then use the product to download a specific track and date afterwards.
For example, to purchase a Classic PP or plan, and change your card information, select the link below:
Select the option you wish to purchase.
This will bring you to the online shopping cart. Select "Checkout."
Confirm your billing information, and then go to "Payment".
You will see an option on that page to change your credit card (see screenshot, below). Once you do so, it will save the new card information and you should be able to download subsequent products directly.