WilfredRoy It was announced to be released on August during NP3 launch but still no bread crumbs.
I think you got that mixed up quite a bit:
There was a sign-up for a closed-beta test exclusive for Nothing Phone (3) owners in early August.
The closed beta testing was expected to start in late August if I remember correctly and a first public beta was scheduled for sometime September.
So there is a good chance of seeing more new in the next two weeks. However cobsidering beta testing will just start, I wouldn’t expect the final, public release of OS 4.0 before November.