Those who use the Self Service Buy option can modify their billing information by first logging into AppDynamics.com, then navigate to the account page, and click on the subscriptions box.
On the subscriptions page, select your SaaS license and click the 'Change Payment Method' button.
Update your billing information and click the 'Submit Change' button.
Click the continue button to confirm the update.
You will receive an email with the subject 'You have updated your AppDynamics billing information', which will contain your billing address and payment details.