That is EXACTLY the problem - he is up TOO long between naps. Not because I keep him up. Because he does not / cannot fall asleep!
He is turning 3 months on Saturday, and his A time should be 1h30min max. But at days like these (it's lasting for a week now! and happened before as well) no matter what I do - hold, rock, walk, sing, sling, swing - nothing makes him sleep
His mantra cry turns into my karma every single time. In 3 months, we have yet to see him fall asleep with the mantra cry. No way. After 10-15 min he works himself up to outloud crying and I have to step in.
The A time in the darkened room is only the very first A time in a day, simply cuz I'm not yet ready to get up, so we play on our bed.
For WD I take him to the room, talking quietly, we say good night to the sun and close the shades, I hold him walking and humming a lullaby (about 5 min), put him in his swing and turn it on. Usually he falls asleep in the next 15 min of swinging.
Of course, sometimes I have to shush and hold him longer cuz he is crying. Or he may start crying when I put him in swing. Or he does not fall asleep and then 20 min of holding follows. You know, days don't go the same way