[Heaven's Night]

Taxer, 

I have wondered whether 38B (my size also) is the furthest I'll get with breast development even with the aid of HRT. I'll be happy with 38B if I can get the other feminization changes like softer face/skin, etc.

It's hard to say.  Genetics is a big factor.  They say that how big your mother was can determine how big you may get.  I started later in life - maybe if I started a lot earlier they may have grown bigger

It can give some idea, but then there's many who have surpassed their relatives too... So its not always written in stone.