The formal announcement of the Google Pixel 6 and Pixel 6 Pro smartphones took place (unexpectedly for many) at the very beginning of August, and the full-fledged premiere could happen on September 13th. At least this date is given by a Chinese informant who has a good track record in the form of confirmed leaks.
There are doubts, however. The point is that Pixel smartphones have never been officially sold in China – only in Taiwan. In addition, while this date has been announced for the first time, there is no more confirmation. Finally, this date is not very consistent with the dates of announcements of previous Pixel smartphones – a premiere in October would have looked much more logical. In short, these details can be taken into account, but you should not rely heavily on the fact that the Pixel 6 and Pixel 6 pro will be presented so early.
Also, the source gives the dates of announcements of other September new products. The complete graph looks like this: