My DD was on the exact same number of bfs as your DS at his age, except she would only rarely wake up during the night. And she has bf up until nearly four years of age, so I wouldn't worry!

He is a big boy now (at least, he thinks he is!) and he knows where to find you and your bbs when he wants them. Just don't be surprised if he suddenly changes his mind and is back to you every couple of hours in a month's time!