I've clocked LO at 7 - 9 hours consistently in the last few weeks for his overnight sleep. Naptimes usually range from 2 - 4 hours over the 3 nap (possibly a catnap depending on how well he sleeps and is up). When we co-slept and he fed at the boob whenever he wanted, he would range around 8 - 14 hours with night and day and his longest sleep stretch was in the 4 hour range and the shortest in the 2 hour range. In the last month, the total day and night hours haven't been too different, although the sleep stretches have gone down to lots of 2s and 1 hour stretches.
For overnight, when LO would get up, I'd change him by the light of my cell phone. The light was mostly for snapping buttons together and making sure the diaper was pee only. After that, I'd pick LO up and feed both sides, then put him back the second he was done. Room was entirely dark. I'd only sing to him the lullaby that I use to put him down the last minute or two and then right as I put him down and a minute or two after to help him fall asleep. (Mostly to condition him the "lullaby means it's sleep time".) When we don't change LO after 4 - 5 hours he's usually soaked through his diaper and clothes and wakes from that discomfort, so I've tried to change him every 3'ish hours when he eats to eliminate that as a wake possibility.