If you farm like this, you still do not need increase in reply time, bc you will have a lot of time skips. And these fill up your replies .
According to sizing charts it does. They are called sister sizes. Even famous Victorias Secret has a faq about that.
This is not to say, that those sister sizes are equally good fitting. But there might be many out there wearing the "wrong" size and when asked would give a misleading cup size as an answer. Of course here the devs are just making mistakes.. But there might be real girls and woman out there wearing an "A" but are wearing two sister sizes down and would actually be better fitted with a "C".