Congratz on starting HRT =)
Well it depends for everyone to be honest but for me changes have been the following for breast:
-5 days in my nipples were errect
-17 days in my nipples/breast zone was puffy and sore
-24 days in breast buds started to form and areola started to expand a little
Up until 2 week ago breast buds kept taking size until it reached 2 inch diameter.
Areolas are 1.5 inch diameter for me.
Right now nothing is happening, Waiting for next spurt.

Like i said it is a YMMV thing everyone here will say different things about changes but it surely does happen at some point ( areola to get wider)
Congratz again on starting hormones!