Yes, Piano does support the Account Updater functionality of Braintree.
Please note, that this feature needs to be enabled directly in your Braintree account.
As we don't store that credit card data on our end, we only save a payment token with the tokenized information about the payment method. This means, that instead of the credit card number, expiration date, CVV and any other payment information, we only store an alphanumeric payment token that Braintree provides. This token does not contain any sensitive data but allows Braintree to identify what card data they need to use in order to process the transaction.
Now, in case the Account updater functionality is enabled, we are able to retrieve new data with the help of the payment token from Braintree (for example if the credit card has a new expiration date), thus enabling us to charge the payment method and for the payment to be processed successfully.
If this feature is disabled in Braintree, we would not be able to charge the payment method, as the expiration date of the credit card is in the past.
But enabling this functionality will not automatically update the new payment method information on Piano's end. So the expiration date of the credit card will still be shown as if it were in the past in the My Account section or in the Piano dashboard. Only in your Braintree account will you be able to see the updated, future expiration date.