I had an issue earlier this year when flying LAS-LAX-IAD-YYZ (don't ask!). There was a crew-related delay of 2+ hours on the LAX-IAD segment that would make me miss my ongoing connection.

I had a UA-issued P class ticket and was originally booked on a Polaris 772. Asked to be rebooked on a non-stop LAX-YYZ flight on AC, and they insisted they could only do it in Y because P class wasn't available - only full J. I refused. They also offered an option on a 739 - also no thanks. I told them to leave things as they were and I'd simply seek my free hotel and $1000 APPR compensation afterwards. The person at the UA desk was quite rude throughout the interaction.

I walked away and was getting a virtual agent on the app when suddenly I got a notification saying I'd been rebooked on the AC flight - in full J.

​​The only thing I can think of that may have made them change their mind is the DPNA code on the reservation. My understanding is that once they see someone is a PWD, there's a lot more flexibility, and that a PWD is second in priority for any sort of rebooking - with an unaccompanied minor being the only other person who would be rebooked ahead of a PWD.

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