Relation of Bra Size to Exercise

Hey everyone. I’ve been exercising heavily for 1+ hours every weekday, and I hoped that since breasts are mostly made of fat, my cup size would decrease as I lost fat elsewhere in my body. I started out last year as a 32F and now I’m a 30G- they went Up a cup size, which was Not what I was trying to get at at All (I’ve even tried to stay away from pec exercises for this reason). Anyone else experience this? Or know how to lessen it? Thanks!