The Flight in was from San Antonio that landed at 1:20 PM EDT on the Aug 18th as flight 7350 and left for Orlando at 1:50 PM EDT as flight 8601.
Likely a charter.
Military charters at WN are 7000-7999 series flight numbers so the 7350 was a DOD charter arriving from SAT.
Charter ferries (deadheading a plane to or from a charter) are 8550-8699 so the 8601 was the deadhead back to pilot/airplane base.
Also, don’t forget that the usual turn-around time for Southwest is 25 to 30 minutes.
Makes sense, the Military knows how to deplane a whole lot more efficiently that civilians and also they probably bussed their own bags too.
The flight attendants could deplane faster if they sounded more like the sargent clearing the bus at basic training too.