Hello,
My son and I are going to LAX on Monday on the 5:40 PM flight (A320) We seats on the window one behind another (row 2 and 3) In F. I just have a fear that UA will do a plane change and make it an A319 with only 2 rows of F meaning that one of us will not have a seat.
How often does this happen?
If it does happen do we get some sort of copensation for sitting in Y with a F ticket?

Thanks
Ben