It is zero growth because they come with 1700 pissed off pilots which is about 300 more than are required. As stated all new deliveries will just replace other airframes. Zero growth and overstaffed. I foresee min pay lines for a LONG time to come. Should just add to the fun.
I don't know how many of the 1700 pilots will be pissed off but I agree with your overstaffing prediction along with a lot of min pay lines. That's why I've found the AAI QOL argument to have very little credence in this merger/acquisition.
Everyone will have more time off which theoretically means higher QOL. The good news is that you'll get more time at home with family. The bad news for the SWA pilots is that they'll see less take home pay - the AAI pilots will see a pay increase that should more than offset a reduction in the number of hours worked.
Once retirements start occurring on a regular basis, most of the retirements will be from the SWA side so that AAI pilots will see their relative seniority increase much more than they would have seen if they had been a standalone carrier.
The only way I see this changing is if Southwest is able to significantly expand block hours. I think they're near the near term market saturation point so I don't see that as likely but I've been wrong plenty of times in the past.