I started introducing it at 9 months and she was weaned and strictly on cows milk from a straw cup by 11.5 months.

I started at a year

Can you pump a bit every day so you have a few bottles by next weekend? Sometimes you can get more milk out hand expressing rather than the pump

“Babies who are exposed to cow’s milk before their first birthday are more likely to be anemic, have diarrhea or vomiting, and/or experience an allergic reaction (the proteins in milk are more numerous than those in other milk products, such as the yogurt). The excessive protein load in cow’s milk can also overload a baby’s kidneys. It is deficient in vitamins C, E, and copper. It is harder to digest as well, often causing intestinal blood loss. A number of studies have also indicated that early introduction of cow’s milk may contribute to the development of Insulin-Dependent Diabetes Mellitus. It may even cause iron-deficiency anemia in some babies, since cow's milk protein can irritate the lining of the stomach and intestine, leading to loss of blood into the stools.”

I personally would just try harder with getting baby to take formula.

Someone said from what I see on baby center “the logic behind it is that some babies have dairy sensitivity, and the nutrients in breastmilk or formula are better suited to human babies” and ссылка “ It is safe to introduce cow's milk at between the ages of nine and 12 months of age. The reason why babies should not drink cow's milk before then is because the proteins present in fluid cow's milk are hard for young infants to tolerate and digest. New infant feeding guidelines were released in early 2014 by Health Canada, Dietitians of Canada, the Breastfeeding Commitee of Canada and the Canadian Pediatric Society stating that homogenized fluid milk should be introduced between the ages of nine and 12 months of age. At around one year of age, I encourage moms to continue breastfeeding if they are already, even with the introduction of cow’s milk. Some moms choose to delay the introduction of cow's milk because they are still breastfeeding two to three times a day and that is fine. If your baby is on formula, you can slowly transition to homogenized cow’s milk (assuming your baby doesn’t have a milk allergy) at around one year. You don’t want rush this transition because your baby’s digestive system needs time to adapt to the new proteins and other nutrients present in fluid milk. Start with one to two tablespoons a day and slowly increase until fully transitioned. Again, you can continue to breastfeed as long as possible. Your baby should be having two to three cups (16-24 oz) of milk per day maximum until the age of two and then should decrease down to two cups max. (16 oz). If your baby is still nursing, he may not need as much of any. Milk should be offered ideally in an open cup or straw cup preferably at meals or just after. This is to make sure that your baby or toddler is not filling up on milk before a meal (ruining their appetite). Offer water freely in between meals. Even though it may be a tough transition, try to encourage cups and not bottles, especially after 14-15 months of age. If your baby is allergic to milk or lactose intolerant, you may want to consider keeping your baby on formula or a follow-up formula until the age of 2 to ensure proper nutrition. There are soy varieties or hydrolyzed protein/hypoallergenic varieties out there for babies with allergies or intolerances. There is also lactose-free homogenized milk available at most grocery stores which is the best alternative for those babies or toddlers with a lactose intolerance. You should offer the same quantity as you would cow’s milk. If you're unsure, make an appointment with a pediatric dietitian who can offer personalized advice. ”

She’s 10 months or?

Yea they can have trouble digesting or even get sick or gas so tread carefully