Ok - so we are trying the 1.5 nap today, not by choice.
So here is the routine for today.
Crying 5:05am not sure when he went back to sleep, or for how long.
Woke for the day 7:06
Nap 12:45-2:15 woke on his own. Pretty sure it was an OT nap as he woke a few times during the nap, but he didn't need me at all.
Bed 5.5 hours later at 7:45. No fuss. Asleep around 8:00.
Got my fingers crossed.