Experiences with bottles past 12 months?

I’m just wondering, for those who didn’t forcefully cut their little one off the bottle (at least not right away) - how long did it last, did it cause any issues to continue, etc?

And you don’t need to take this into account for your answer because I really am broadly looking for general experiences, but I’m just including it in case someone judges me for not cutting him off: my son is 14 months and has some minor GI issues that basically mean that I’m always just grateful for him to get whatever nutrition he’s willing to take however he wants to take it, and he still has 3-5 bottles a day. Sometimes only an ounce, sometimes up to 6-8 (usually this is overnight or if he had a hard time taking a meal). He does know how to drink out of a cup, but if he drinks more than an ounce of liquid from a cup he tends to vomit most of it back up.