I just installed Beta 7 of the Big Sur operating system. The install did not take as long as some others, perhaps it was somewhat smaller. There are no obvious changes in Beta 7, it runs fine. My main workflow Apps work pretty well so far. When Apple gets to a Beta 7 the operating system involved is close to release. I don’t know if Big Sur will be released in September or not. I am inclined to think the release will be in early October sometime.