In the run up to the Full Moon at Michaelmas on Sept 29th, I thought this was a great article. It’s short and to the point.
Also, this upcoming full moon promises to be strong so it wouldn’t hurt to get your Michaelmas playlist going, well, because you never know. 
https://forum.enlightenedstates.com/t/michaelmas/44182?u=vmms
ETA: I also just found this work of Rudolf Steiner on Michaelmas. At 171pages, I’ve not read it and so can’t speak to its veracity. Still its an intriguing find. 
https://www.waldorflibrary.org/images/stories/articles/wjp15updated.pdf