I've changed, via the UE behaviour, the From address to email@example.com but when I open waue_contact-led-warehouse-confirm_1.php I can see no mention of the To address, firstname.lastname@example.org. I attach it again, with email@example.com added.
Something is definitely not working between the behaviour window and updating the corresponding waue_ file.
If I remove the dynamic reply address altogether then the forms sends so I'm really not convinced that this is a server issue.
Hope you can help