I was wondering if this route has staying power against Delta, or if Southwest would likely delete it? It looks like the earliest flight and late return is still on AirTran metal, so any business pax, likely higher yield traffic, aren't using Southwest metal yet.

I only bring it up because Southwest deleted a number of short-haul routes that were deemed "driveable" in the past, including CLT-ATL, and didn't start BNA-ATL.

I drove this route and it was at some points a six-lane highway to eight-lane and didn't have to deal with tolls. Motorists were driving 85mph. It was not like Philly to Pittsburgh with mountainous terrain. I saw MegaBus was covering the Jacksonville to Atlanta route as well. The ATL experience is also lengthy, from the return your rental car to the plane you are on actually taking off, so I'm not sure if that is a factor for business pax, who might opt to drive and do the mileage reimbursement from their employer.

LGA and PHL need the connection in ATL the most, LGA-ATL-JAX, but cities north of LGA can connect in BWI. RIC also only connects to JAX via ATL, but not sure if Southwest cares about the RIC to JAX market.

Southwest once flew PHL-JAX but deleted the route, just about the time AirTran was taken over.

Southwest also offers BNA as a connecting point for LGA and PHL pax however, and EWR to JAX is best offered through BNA, so it might have to upgrade BNA-JAX I'm guessing if ATL-JAX were to disappear.