I have my normal back ( which I’m already a notch up on by my first wash), had to go up a cup size and it’s still prone to monoboob! Shortened the straps and will put a stitch in to take the top edge of the cup tighter to reshape and create some separation. The top edge of the cup is also 2 separate layers with no edge on the top one so be aware it may roll if tight clothing is pulled down over it.