That is an old wives' tale. Don't trust that, it doesn't work, and flipping a chicken on their back is dangerous because their ribs compress on their organs, and it can kill them in a second by stopping their heart or lungs.
It is too early to tell, update at six weeks. However, I have to tell you that is not a Brahma. Brahmas have pea combs, while your chick has a straight comb.