When we switched Tyler, we transitioned him to whole milk at the same time. Gave it to him in bottles instead of formula for a couple of days to make sure he'd drink it, then started dropping bottles and replacing with either a meal or snack with a sippy of milk. I think we dropped a bottle every few days to give his appetite a chance to adjust, and we kept the bedtime bottle for a couple of extra months. While we were transitioning, he barely drank anything from the sippy, so we made up for it by offering it to him frequently during the day (insulated sippies are good for this if she'll drinki from them) and offering more cheese and yogurt. A week or 2 after we dropped the last daytime bottle, he started to drink quite a bit more from the sippy, like he suddenly realized that was how he was supposed to drink stuff now!
