Google updated Android 13 in September for Pixel devices
It seems that the rumors about the September update for Pixel devices being Android 14 are not true, as Google recently released the Android 13 update for supported devices (from the Pixel 4a 5G and Pixel 5 onwards).
We initially assumed the final version of Android 14 would come out in August based on the timeline Google kept showing for months on end during its beta testing of the upcoming OS version. But then in August the company clumsily tacked on another beta to the release cycle, and there were then a couple more bug fixing releases, and here we are, in mid-September already, without the release going live.
So maybe the company has indeed decided to hold it until early October, which is also when it's officially announcing new devices.
Anyway, today's update arrives as build TQ3A.230901.001 on most devices, though some regional and carrier variants might have a one letter plus one number suffix added to that. This update isn't one of those 'feature drops' that arrive every three months with new functionalities, it's just one that fixes bugs and security issues.
As usual with Google releases, it might take a few days (if not more) for all supported devices out there in the wild to receive the update notification.