Hi Taylor,my daughter was exactly 11 mths when we switched to cows` milk. We didn`t plan to,it just happened that she was taking less and less formula and I had to tip out whatever was left over,and I thought,well that`s it, I`m not paying for formula milk and then chucking it out,and I started to give her half formula half full fat milk,and then gradually just full fat milk. I found she upped her milk intake by 2/3!!!
Good luck.