Yes, that's exactly what it does. The 2nd row folds down flat and then it can also flip forward. They demo this in an Instagram video: Design - @rivianofficialCorrect me if am wrong, but doesn't the second row seats adjust forward and flip up to let people in the 3rd row????? Just had a new Chevy Tahoe and drove it to Truckee CA. Access to the 3rd wasn't problem for the grown adults seated in the 3rd row. Rivian has to have this dialed in.
The thing I noticed most though is how little leg room there is in the 3rd row... yikes! For a vehicle as long and square as the R1S is I was surprised to see how tight the 3rd row was. Maybe they should have made the frunk a bit smaller and lengthened the interior cabin 2-3 inches.