Originally Posted by
dmbolp
Can't use it until T-24
When can Customers add Upgraded Boarding to their itinerary?
Upgraded Boarding is available for purchase 24 hours before the flight’s scheduled departure time depending on availability. Upgraded Boarding sales will end 30 minutes before departure.
https://www.southwest.com/help/day-o...ng-information
And you have to "check in" to buy it.