When to drop night feeds

My baby is 3 mth + now. Nowadays i wake him up if he slept longer than 6hrs at night. He drinks milk at 5.30 - 6pm. Went to bed at 7.30pm. I woke him up for milk at 10.30pm and 4.30am. My husband say i should wake him up maximum 4hrs. But i feel that i am disturbing his sleep. Mummies, how often should i wake a 3mth + old baby up for milk at night? When do u all drop nights feed for your babies?