If you are traveling with more than 2 customers under a single itinerary, the booking counts as an individual. So, if you wish for Southwest Airlines change flight options for one passenger among them, this is not possible. Changing a flight is simple with Southwest, but only one passenger from an itinerary of three or four can not change his flight. The only resort left is to cancel and rebook flights for everyone in this situation. For more clear options, you can call Southwest in advance and inform them about the situation. Depending on the circumstances, they may offer you something that is beneficial to both of you!

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