Frontier: For those scheduled to travel between June 27 and July 4 and purchased tickets on or before June 27, one free itinerary change is allowed but it must be made by June 30. Travel must be completed by July 7 or a fare difference may apply. Passengers must make changes by phone at (800) 432-1359.
United: For those scheduled to travel between June 27 and July 2, the change fee (and fare difference, if any) will be waived if travel begins by July 9. For later flights, a fare difference may apply.