You certainly can!
Log in to your Paypa Plane account via our App, or at client.paypaplane.com to view all existing agreements. Click "VIEW" to enter any agreement, then click the green 'CHANGE PAYMENT METHOD" button to enter your Visa, Mastercard or Bank Account.
Once added, you can view all exisiting payment methods by clicking the small green menu button (bottom right hand corner) then clicking "Payment Methods".
This will show you all your payment methods, allowing you to switch back and forth between them as much as you like!