The end of August is good because the local kids are back in school by then, but I don't think there's a good answer for how/when until we see how the
Lightning Lane and Genie app are going to affect this. When the local kids are back in school, Sundays have light attendance everywhere at WDW.
Right now, if you miss the 7 am boarding passes, the virtual queue requests open again at 1 pm for anyone inside the park and it's only people with reservations for that day because nobody can park hop before 2 pm. We (I'm local w/AP) were able to get a boarding group for the first time ever on Sunday the 22nd. We arrived around 5 pm, got Group #177 and we in the preshow at 8 pm. (Our first time on Flight of Passage was about 18 months after it opened, so I really didn't expect it to be sooner.) I've been watching the boarding group situation this week. Tonight, queue requests closed at about 7 pm. The last group was #154. On Thursday, the queue closed at 1:45 pm and they only had 133 groups. Monday it closed at 2:57 and they had 150 groups.
Just remember it's hot as Hades and you may have hurricane issues in late August, but the crowds are generally smaller.
[/Right. I am nervous about going then because of the hurricane season. I hope that by the time we go, it will be easier to get a boarding pass and all of the kinks will be worked out of the Genie. I find it so much more difficult to plan a trip there compared to the last few times we went many years ago. Thanks.