In Jan I had a Monday return flight booked originally with Southwest, something came up that I really wanted to be back for on Sunday but the flight to KC that would get me there in time was at 9:35 am, it was also a Southwest flight. I booked it but also kept the 1st flight just in case I didn't make it to the Sunday flight. Thankfully with Southwest you aren't penalized and would you the credit later for the flight I didn't use. We did the self assist debarkment, got in line around 6:30, line started moving around 7:00 and I was in the taxi by 7:35 and at the airport at 7:55. Worked out for me this time but did cause me some anxiety.