Sorry I've been MIA. Haven't fully caught up on everyone's posts.
I was out of town for a long weekend last week and DH had J. He did 2 nap days while I was gone with no issue, but when I got back, we were back to faffing til 9pm with 2 nap days, etc.
I've pushed to 1 nap for about a week now and I think we may be there. She was hovering around 4.5 A time and I nudged her along and now she's handling 5+ A times without much issue (although she's always handled OT well). Yesterday was a real test because she had a shorter nap from 11:30 til 1pm (we've been getting 2.5 hrs +). I'd planned to put her down for a 2nd nap but we got held up at an appt. so I couldn't. I put her down for bed at 6:30 and she slept til 6:10am.
With DD1, after we'd reached 1 nap, I set her nap time and then did A times for BT as she was sensitive to OT for bed. So, for instance, I set a 12pm nap regardless of WU, then did 5 hrs to bt depending on nap length. I may do something similar with J now. 11:30 is working well for the nap. I'd like to nudge it to 12 or later, but she seems like she may need a longer A til bed. Will probably give it another couple weeks.
Have to say, it's nice to be closer! This transition is so tricky!