How does working full time and breastfeeding work (toddler)?

I am breastfeeding my 17 month old and will be returning to work shortly. She is breastfed on demand, and it varies day to day. I have never had engorgement and have always had a lower supply. Will I dry up? She loves breastfeeding. It is literally one of her favourite things. I am still very open/willing to nurse her before/after work, through the night. I'll be away for about 8 hours of the day.