But what if they did :D ???

Personally, I'd see what my schedule looked like. If they call and left a message, but your cellphone provider was messed up and the message doesn't come through for 5 hours, it's on you. They usually put a note on your schedule similar to "LM at 1510 for ROT 0553/24" which is their indication that the left a message. That covers them..

For me, it's not worth a call with the Chief pilot or losing a day's pay because I wanted to argue whether they left a voicemail or not.

I of course was kidding. But great advice.

Well they did it to me. I called back and the trip was dropped because the notified me within 12 hours of report. I just happened to see the missed call.

Did you talk to ALPA? File a grievance? If they didn’t do what they were supposed to, hold them accountable.

They accidentally called with less than contractual hours, and if I understand correctly they realized it and didn't leave a message at that point. I don't see anything firm that they would have done that would be a violation.

They called and didn’t leave a message. I called back and got flak from the scheduler until I was transferred to a supervisor. The supervisor said yep you weren’t contacted with enough time the trip is off my schedule. So no harm no foul. I then thought about what would have happened if I didn’t see the missed call and there wasn’t a message. Did that count as contact even though it was within the 12 hours? The schedule reference handbook and PWA don’t state what counts as contact that I can find. This is why I ask the question.

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.

What is a “standard scheduling number?”

deleted, but they are available on deltanet