Promotion after making weight?

My friend in the Army is an E2 but has been promotable for some time, but he has been overweight. He will be getting deployed shortly and thinks he will 'make weight' before that. He wonders if they will promote him directly to E4 when he makes weight instead of just to E3? I guess he is thinking that if he was thinner he would have make E4 by now. Do you think that they will promote him to E4 or E3 when he makes weight? Thank you.