If you book a flight on line at SWA, confirm the reservation and a few days later the fare drops on the same flight you are booked on. If you go to your account, see the flight, go to change flight, click the same day, it will say "current flight" and not allow you to make a change (On the specific flight) for a lower fare.Canceling and rebooking might be a different story. Haven't done that. Wasn't worth the trouble for a few dollars.

United does the same. But if you cancel (and get a future flight credit) and rebook you can book the same flight at a lower fare.

Don't know what the two free changes are? Can someone explain. Thanks