Daycare feeding

Mamas who nurse and supplement. I went back to work after 12 weeks 8/15. Since then each feed he gets 1 bottle pumped milk, and 1 bottle formula, to mimic my nursing and bottle of formula. I just went part time and he just changed rooms. He gets 6 oz a feed(3 at daycare) plus solids since he is 7.5 months. Should I change it to 2 of the 6 oz breast milk bottles and alternate with middle being 6 oz formula or keep as is?