This board is such an amazing resource for information. Thank you. Looks like I should watch what happens to the numbers between now and 72 hours before the flight.

By the way, I had a message to call CO a couple of weeks ago because of a change to the itinerary. (It was minor...a NW flight was 7 minutes earlier). I asked how full the flight was and the reservations person said overbooked. I asked how overbooked and he just replied "it's overbooked." That's partly why I was curious.