The billing page is split into 3 sections:
Plan Information
Current Plans - View which subscriptions you are currently paying for. You will see the subtotal for each subscription plus the total of all subscriptions. You will also be able to cancel subscriptions from this section.
Payment Method
Card Details - View your current default payment method. This card will be used for ALL subscriptions.
Update Default Payment Method - This will allow you to change your default card on file.
NOTE: Updating your default payment method will update the card on file for ALL subscriptions. This also applies if you sign up for a new subscription using a different card.
Invoices
Invoice Copies - View and download paid invoices.