Our lo started waking 45 min into his night time sleep around the same time. We changed his nap routine from 3 1.5 (when we could extend them!) and a catnap, to 2, 1.5-2 hour naps (again when we can extend them) and no more than an hour catnap later in the day. He has his second nap from about 12:15-2:15 and the short nap between 4-5. We wake him up if he is still asleep shortly after 5 because we learned the hard way that if he naps much past then, he is a bear to put down to sleep! I feed him at 5pm (takes close to 30min) activities that are low-key (ie. just looking around on blanket on the floor or a walk in the stroller) bath at 6:30, feed at 7:00 in his nursury and to sleep by 7:30. I know he's up 2.5 hours but as long as we keep things low key for that last hour with the bath and last feed he makes it through quite well. As soon as we did this (we changed up that catnap time a few days ago) he has slept through the 45 min mark each night for the first time in 3 weeks. Good luck! Oh, and my girlfriend's lo had the same problem at the same age, too, so it makes me wonder if it is a developmental blip in their development at that age, maybe a signal to us that it's time to change their naps.....? I wonder this because this new nap routine closely resembles that of the four hour EASY....