Hey Maya, sorry if I have said this before but I think if you are doing set naps you need to more think about the nap times than the A times. Was it just one night that DS was hard to put to bed? Could be for a range of reasons, not necessarily his routine. I personally would stick with the 1.5hr morning nap at whatever time you have set and the pm nap at whatever time you have set, leaving him to sleep no later than 4/4:15pm and BT at 7pm. That is just what happened to work for us for many months when DD was doing 2 great naps (before she hit 2:1 ouch!)