Equal visitation while establishing breastfeeding

So my baby's dad and I split up about a week ago and my due date is In 3 weeks. He insists our baby spend equal time at both houses from the get go. I strongly want to breastfeed so I told him that might not be realistic until I get a good supply and routine with breastfeeding and he is just not having it. He said he would just give her formula and she can still spend half of the time with him. I don't want to argue with him but I don't know what to do. Suggestions and advice please?