I can't believe we're having a discussion about re-interviewing. That may have been the case with previous airlines that SWA dealt with, but those airlines were made up of a meager handful of airplanes, or were on liquidation's doorstep.
It's a whole different dynamic with AirTran. With them, you're talking about a profitable company with 137 aircraft, a bunch more on order, and 1700+ unionized pilots.
If you merge with the AirTran network on Monday, you have to fly that network on Tuesday or else you will be in bankruptcy court by Friday. To do that you need the pilots who are currently flying those airplanes to stay with those airplanes.
Therefore, re-interviewing is illogical. It will be a merged seniority list with the new airline being very formidable.
The wild card is Delta. Would Delta want to go up against such a combined carrier? Would they abandon the NWA deal and instead shift all resources into perhaps a bidding war with SWA in order to merge with AirTran and thereby keep SWA out of their Atlanta backyard? Surely the DOT would have something to say about this. But Delta weilds a lot of political power with the city of Atlanta who in turn could carry some heavy weight up to DC to do battle with the Feds.
Only time will tell...