Currently booked on the first SW flight of the day, on an internet, one-way fare. At the time we booked, the later flight (which we preferred) wasn't available in the internet one-way "bucket" so we went for the less expensive and less desirable (to us) time. This later flight is now become available at the internet one-way price surprise surprise - can we switch flights since they're the same fare bucket/price/date? Anyone done this? TIA!