When to wean from bottles - 1 yr old

[Eniala]

My son has 3 bottles a day at daycare with 4 oz. each and he just turned 1 year old. When should I worry about weaning him from bottles? He drinks form a sippy with meals but I dont think he gets near the same amount as from his bottles. We did BLW so he eats 3 meals a day on top of his bottles. I am going throgh my frozen milk stash and will soon be mixing in cows milk to start transitioning him. I have no idea when he should be off bottles at daycare, and would I just send milk in a sippy to be offered with his meals?