What is this field for?
PRO can collect an alternative notification email address in the form. This allows the customer to specify a different address for confirmations and later status updates without changing the billing details used for order verification.
Important distinction
This address is used for communication about the withdrawal. The actual order matching continues to use the configured verification method.
Testing
After enabling the option, test both the receipt email and the decision email to make sure it is clear which customer address is actually being used.