i can't remember exactly, but it seems for us, we dropped one feeding at about 8 weeks and the last feeding at 14 weeks. you little guy may need to hang onto them a little longer since he was premature. for us, we knew it was time to drop the feed when she'd barely suck for a min or two them fall asleep. so when she would wake for that feed, we'd just let her fuss. she never really cried, but would just wake and fuss/whine on and off for about 30 mins. she did this for a night or two then started sleeping through. i realize not all babies are that easy, but that is how we did it.