It is much, much less busy. I always go in fall. Last week of Sept is still a bit too hot for me so prefer end of October or even November. There is a bump in activity over fall break, which for southern schools seems to usually be around the week Columbus Day occurs, which is Oct 8th this year. It’s busier but not anything like spring break or summer. Huge drop off in hurricane risk past Nov 1, although they can still occur. Also, the weather is awesome during the fall. Years ago when I first started coming to 30A, I asked locals what they thought was the best time of year, and they all said fall.