If I could make a suggestion, I would recommend (eventually) moving away from cup sizes for bust, and transition to a simple number system like Volume. Cup sizes can vary by country, and also by themselves aren't actually very descriptive, since band size can also have a huge effect. Saying "GG cup" really doesn't tell much, and also the upper limit is forced by how many sizes you want to manually program in.
Volume is just numbers, so you theoretically could just have it tracked like weight and not need to worry about people hitting an upper limit.