Rest easy, imminent travelers. We went last year, Sep 16-21. Got my ADRs about 90 to 60 days out, some later, no problem. Left Monday late am from Pittsburgh (pulled DS 7 from school, didn't hurt his education at all, and may have helped) and got into POP by 2 pm. By 3 pm, we we're checked in and DW and DD stayed to nap while DS and I went to BB. Not overly crowded, nice sunny day. Went and gathered DFamily from POP and went to Epcot for 7 pm TS at R&C for Illuminations. NO crowd. Walked on Spaceship Earth, prior to dinner, no wait.
Tuesday MK, got there about 30-60 minutes after rope drop. NO crowd. Went to Tomorrowland first, and saw Stitch ALONE walking about. Got many pics and autograph. Walk on Space Mountain twice with NO wait. (Light rain for about 30 minutes at about 10 am helped. Rode Buzz, 5 minute wait. Stitch, 5 min. Worst line was Speedway, about 20-30 minutes. Did all of Toontown and most of Fantasyland by 2 pm CRT lunch. Minimal waits on Fantasyland rides, most was about 10 minutes for small world. Walk on to Haunted Mansion, Rode BMTRR with minimal wait and again right after with FP. Jungle Cruise, 10 minute wait, max. Fantastic Day.
MGM on Wed, low crowds, walk on ToT twice, no wait. Star Tours twice, no wait.
AK on Thu, low crowds, (Rained about 4 so we left, but did everything (almost) by then anyway). Safari, 15 minut wait, Kali, twice, 10 minutes or so. Dinosaur, walk on.
TL and EPCOT on Fri, low crowds, used FP and walked on other rides. M:S 5 min, test track 10 min. El Rio whatever, and Mael something, walk ons.
Sat at MK prior to depart, LOW crowds, unbelievable. Walk on Pirates, 5 min wait for Splash Mtn, twice. Wait for Buzz/Incredibles, Stitch signatures/pics, 10 minutes.
Too much food, very little crowds. FANTASTIC TRIP.
The shortened operating hours is more than made up for in the lack of crowds.
ENJOY.
Even a bad day at Disney beats a good day at work.