It all depends on how much testosterone is in the body. That's why there needs to be an anti androgen as well. The body will fight between the estrogen and testosterone. My T was high for about the first year and it took about 9 months before I felt breast buds and another year approx to get to a B cup but still growing.
So to your question, results vary. 1,2,3,4,5,6,7,8,9,10 + months.
Stardust