oh, honey ... they'll go down. and, i regret to inform you, they'll resemble tube socks.
i would suggest that you wait until you're completely done with nursing before buying any new bras, girlfriend. your boobs will not be the same. good to get some ideas on potential bras, but what fits now will likely NOT fit after you wean.
p.s. what's really scary -- i am most definitely NOT endowed, and i still get tube sock boobs after weaning a baby. lol. little baby tube socks, but still.......