The way Southwest does credits with points can be confusing, so please don't feel stupid! When you change flights or get a credit with pts, the original pts will be refunded and the new lower price pts will be deducted. If I'm understanding correctly, you originally bought a flight for 12/3 for 30,358 pts/pp. When you changed to the 12/2 flight, 30,358 pts/pp were refunded and 24,953 pts/pp were deducted for the new flight. When you then changed flight times for 12/2, you were refunded 24,953 pts/pp and charged 27,877 pts/pp. They not only add back all pts for a credit and then deduct all pts for the new flights, but they also do it for each person, which is why you see 2 redemptions for each of the purchases as well as the refunds. I think it'd be easier for them to just subtract or add the difference when changing a flight or getting a credit because it does get confusing the way they do it. Hope this helps and that I'm understanding what you did

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