They have done that. They were fishing for IAs a while back when I got a call that I ignored and it wasn't a standard scheduling number. Minutes later my wife (my back up number) gets a call from the same non-delta scheduling number. She answered and it was a scheduler looking for me. She knows how to handle that situation and informed them I wasn't available. So it has been done in the past and I think they cleaned that up in the PWA awhile ago but... when you absolutely positively have to get it there overnight, the PWA is merely a suggestion. Violations happen... oops.