Just wondering when they do have catnaps say for 20 minutes, what is their awake time before bedtime ?
There may be members of the community who could give you an idea of this but in my experience LOs are all so different it's impossible to say. You might get some ideas on the 2-1 support thread?
I think if you record how things go for your own LO, how long the CN and how long to bed, looking at fussing or refusal at BT etc then you will be able to gauge it from how he responds. Maybe capping the nap at 10 or 15 mins if there is reluctance at BT? I know some end up with a super late BT is they CN which is why I say I can't really answer this. Sorry.
It's great you managed to get back to a decent WU and can go to a one nap day - good luck
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Also this waking up after 1:20 mins.. Could this mean UT? He is currently on 5h45 A time ? Should I increase a bit ?
It could well be, yes. It may help to try another 10-15 mins on the A to see if he can transition because it does look like he is tired enough to go back with help but not alone. A longer A time also helps to just get through the day as it moves the nap later too. If you try a longer A and end up with OT wake ups you can always bring it back a bit again, how about trying for 3-5 days?
You're doing really well! No where near as tricky as our 2-1!