I have a mileage run booked for this Friday on United. When I booked it (last month), I specifically wanted a few segments on the 787. United just changed the aircraft on the IAH-LAX segment from a 787 to a 767-400ER, which was expected. Now, knowing that the 787 isn't part of my trip, I would like to modify my return flight, to allow a longer stay in L.A. As it stands, I arrive at LAX at about 7:30pm Friday, and depart LAX at midnight for IAH. I would maybe like to extend my stay in L.A. about another 12 hours or so, seeing as I don't need to catch a certain 787 anymore. My question is this... Would United consider my plight about booking that trip based on flying on the 787, and let me change my return because the 787 is grounded or will they just tell me tough luck, and I would need to pay for a change? I just figure since I am not trying to fly specifically on the 787 now, I might as well take my time, and not rush back. Maybe I am looking at this the wrong way, but I just thought I would try. Any insight would be appreciated. Thanks!