When you use the "Change Flight" function on a round-trip, you'll need to select both the outbound and return flight to change, otherwise the destination will be grayed out. @dfwskier wrote: Remember that changing a trip will require you to pay exactly the same fare regardless of whether you change an existing trip or book a new one. Given that, pick the easiest way to proceed. I'm not sure what you're trying to say. If you change to a more expensive flight, the system will show you the additional $ or points needed. If the flight is less expensive, the system will show you the credit you'll receive.
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