I posted this in the Breastfeeding community as well, but I figured I'd post her as well, since this community tends to get more visitors.
I pump twice a day at work, and usually get around 14-15 oz out of those two sessions, so I bring 2 8 oz storage bottles with me and that's always been enough. But my breasts are apparently on overdrive today, and I just got 14 oz (!!) out of just the first session.