Southwest does not charge fees to change or cancel a flight.
While prices fluctuate, certain timeframes historically offer better value: when to buy southwest flights
Credits for "Wanna Get Away" fares never expire. However, note that if you paid with cash, the credit is typically tied to the original passenger; if you paid with points, the difference is simply refunded to your account. Optimal Booking Windows Southwest does not charge fees to change or cancel a flight
If a fare decreases after you buy it, you can "change" your flight to the exact same one at the lower price and receive a credit for the difference. if you paid with points