Interesting topic. I'm AA Gold and booked a mixed itinerary MCO-LAS on US because I couldn't get it on AA. I'm US going out and AA coming back.

The problem I have now is my LAS-MCO return was booked for noonish on April 1st, and now I have a meeting at 3PM so I'm going to need to grab a later flight. I was hoping to just do a same day standby. There are currently a lot more seats open on AA flights that evening. Can I do that for both US and AA flights? Does anyone have experience with doing that?

Or am I better off ponying up the extra $250 to just change the flight now rather than chance it?