https://www.gamespot.com/articles/ps-plus-september-freebie-destiny-2-available-now-/1100-6461458/

In an unusual move, Sony has released one of September's free PlayStation Plus games on PS4 early. Rather than wait for the first Tuesday of the month as usual (September 4, in this case), Sony has both announced the full lineup and offered one of the games for free right away: Destiny 2, which just got a massive pre-DLC update.