Back to work

I am due to go back to work in the next 2 weeks and my baby will be just under 3 months old. Right now his schedule consists of breastfeeding at 8:00 AM, 11:00 AM, 2:00 PM, and 4:30 PM. Then he has his bedtime bottle of breast milk at 7:00 where he usually has 5oz sometimes 6 if he’s extra hungry. When I go back to work I obviously won’t be able to breast feed him all day so I’ll pump at work and send bottles to daycare. I’m wondering how many oz I should be putting in each bottle to send him with? It sound like most EB babies eat a lot more often, but he only eats those 5 times per day. He sleeps from about 8:30 PM to 8:00 AM every day and he’s done that since about 7 weeks. I would like him to keep sleeping through the night so I want to make sure he’s getting all of his calories in during the day. He usually only finishes 5 oz in his bottle at night, but I feel like there’s no way 25 oz is enough for the whole day. Should I try and get him to drink 6 oz so he’s closer to 30 oz for the day? Any advice is appreciated!