This is really getting strange. First, my DD and DGS are meeting me at Orlando in December, with me arriving 20 minutes before them (me on American, they are on Northwest). Then AA changed my schedule, with me arriving 4-1/2 hours after they arrived. This wouldn't do, so I called and they were able to book me on another flight that would arrive 20 minutes AFTER they did.
Today, Northwest advised my DD they had changed her schedule, and she will be arriving 2-1/2 hours BEFORE me. She's going to call and try to get it changed to a different flight that arrives closer to my arrival time -- sounds like a lot of the airlines are doing this schedule change thing!