I have a Symfony project, that is now being tested on live system, and I'm using the delivery_address to prevent sending email to real recipients.
I needed also some exceptions for this, so I have used a very nice delivery_whitelist option (like here).
Right now, the white-listed emails are going both to original target and to delivery_address, but I'd like them to get sent only to the original, white-listed address.
Is that possible in some way?
As @userfuser suggested, here is my slightly altered comment as an answer:
Since your requirement contradicts the semantics of the configuration options, your only option seems to be adding some logic to your mail sending component. I am sure that you will be able to extract the white list and other options programatically so you can build your edge case.