Originally Posted by
Kacee
Yes PN is the instant upgrade class for a B/M upgrade. There have been other reports of the same thing happening recently (PN available but M doesn't clear). I can't explain this for you. Maybe it has something to do with the domestic segment being linked to an international segment (in which case perhaps separating the segments would help). Definitely worth a HUACA.
Thanks. This is the first time I've flown on an M ticket, so its uncharted waters for me...

Surprisingly the CO agent I spoke with when I booked the ticket seemed so sure that neither flight had PN space available...

Thankfully HUACA prevails..
Got my MCI-IAD CR7

confirmed into one of the few remaining F seats, and got my Dad taken care of for his MCO-IAD segment. On his, however, I was surprised to see the following:
Flight:UA1160
Aircraft: Boeing 737-800
Fare Class: United First (PN) - (R class requested)
Meal: Refreshments
No Special Meal Offered.
Not quite sure why the agent waitlisted it for R, but as long as it stays in F, I don't care..
Thanks again ^