cows milk

My baby has been taking 2oz of cows milk mixed with 6oz of breastmilk up until Saturday and I bumped it to 4oz cows milk and 4oz of breastmilk. The past 2-3 days, he has had explosive diarrhea, like out the back and sides, 2 times in the mornings and 1 at night. He also gets that same mixture of milk during daycare and does not have any poops at daycare. Just at home. And it is awful smelling! It is not totally liquid, real smushy though. Has any of the other babies had this happen ? And what did you do? Wait it out? Change to almond milk? Continue to breastfeed? Thanks!!!