Speaking as a midwife the size of your breasts does not have any impact on the amount of milk you produce, girls with tiny breasts can produce more than those with huge boobs as the size of your breasts is not a reflection of the milk holding capacity as the size is largely down to the amount of adipose tissue (fat) in the breasts. Most women have the same amount of glandular tissue which is the bit that makes the milk. I have known women breastfeed after having a BA without any problems, as long as the nipple has not been removed during surgery you shouldnt have any problems. Hope this helps!