Anyone else's boss boss flip out about not have a concrete due date?

I'm 20 + 2 accounting to my LMP, but I've gotten several different due dates from my doctor. I don't mind not having a due date and I actually think it will help me be less anxious when the time gets closer. I won't be having any expectations or whatever. 
BUT, my boss is FLIPPING out because I don't have a due date. He is being absolutely ridiculous. I told him mid July, which is what we are telling everyone. He was not satisfied with that answer and demanded that I tell him the specific date. I told him to just go with July 15 since that's pretty much the exact middle of July, and he got all pissed that I was "giving him false information" and "keeping my due date from him". 
I literally DONT KNOW! "Mid July" is good enough for me. Jeez. It's not like the kid is likely to come on their actual due date anyways.