I phased out the dreamfeed just short of 7 months, as DD started waking up when I fed her, and she was only taking 1-2oz anyway. So I started making sure she took that extra 1-2oz during the day. With breastfeeding it's obviously more difficult to know how DS is taking. Maybe just try it one night and see what happens? You can always add it back the next night. Or if that feels too daunting, you could time how long he's breastfeeding for the DF on a normal night, and shorten by a minute every few nights until he's only BF for 1-2 minutes, and then stop the DF?