Originally Posted by zombietooth

This has not been my experience. During my last IRROPS, I presented the agent with 3 alternate flights with open seats that would get me to my destination on time and was told that they couldn't book me on non-UA flights. 2 were on DL and one was on AA. I asked for a supervisor and was put on hold, with the original agent finally coming back and telling me that the supervisor confirmed the policy. So, I canceled my UA tickets for cash refund and rebooked myself on DL.