I went up about 4 sizes in from the time I was 37 weeks to the time bubs was 6 months old. 3 of those were before she was 8 weeks.
They did slowly get smaller again, but are still not pre-preg size (or rather, weren't when I got preg again lol), over the course of our almost 3 years of BF. I got down to an F.

I ended up an H cup, PITA.

Now I am a GG already, hoping they don't get too much bigger this time around!

There is actually a photo, wish I could post it here cos it is so damn funny (maybe I will post it as secret BB photo on FB ) anyway, it is about day 3 in hossie, milk had come in the night before, and I had fallen asleep with DD swaddled next to me sitting up in the bed. My boob is out because she had been feeding, and my nipple is the size of her face, my boob twice the size of her head! Is a golden moment.