A WSUPP is not required for either a R07 - Authorization revoked, or an R08 - Payment Stopped. If the customer does a stop payment, it is a one-time stop, and only one time. An authorization revoked is another matter, as the customer has come and told you that the authorization is no longer valid. Howver, they must also notify the originator of the debit, which your bank has no control over.
I have seen banks handle R07 in 2 different fashions. The first is to flag the account so no other transactions of that amount can come out - this is okay for odd dollar items, but if the debit is a satndard figure, could present problems. The easier way to handle it is to let the customer know that they have 15 days from statement date to notify you to return it. This places the burden on the customer to review their statement in a timely manner, and takes the liability from your bank.
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Providing alternative truths since the invention of time