Originally Posted by
treyster
Yup, just change flight and pick the exact same flight. You can see the price/point difference before you are committed to the change.
Chris is right, you have to keep tracK of the confirmation number that the reservation is on to use your $$ credit in the future.
The only catch is early birds are issued in chronological order, so when you rebook you move to the end of the early bird line. So instead of getting A22 you might get A37