How to pump 20oz a day!?

Jessie

My 7 month old drinks four 5oz bottles of breast milk while she is at daycare, 7:30am-4:00pm. I pump usually one side at 6am so she can drink from the other side, and then I pump at 9am, 12:00pm and 3:00pm at work. I am barely pumping enough milk for the next day, and have had to use my frozen stash. I added a 3am pumping session but she still wakes up 2-3 times a night to nurse and I want to have milk for her. Im worried I will breeze through my freezer stash in no time!