OK, let's work on this!
First off, wind downs. When you say he doesn't 'do' wind downs, I suspect you mean something like cuddling in the rocker. That's OK -- a wind down doesn't have to be snuggly and quiet. A wind down is really just a cue to your child that a sleep period is coming. At our house? Wind down starts with jumping off the couch 5 times and then daddy throwing LO in the air 5 times.
That's what floats my kids boat, but it is HIS signal that a sleep period is coming. He calms down IMMENSELY after those jumps because we've done it long enough that he knows here comes a sleep period!
Really, just make sure you have some kind of ritual before sleep -- some way of saying 'play time is over. let's get relaxed and ready for sleep.' That may mean you walk around the house and say 'night-night' to familiar/favorite objects. It may mean you look out the window and tell the world night-night. It may mean you just sing a couple of songs while walking, jumping, etc. Whatever. If he doesn't want to sit in your lap for a story, that's OK! Let him roam around the room while you sit and read. Don't worry, he's listening! And if he's not into cuddling you might make sure that the last story you read is ALWAYS the same one and ALWAYS is one that talks about going to sleep. We don't need his body to be still, we just need him to shift gears. Spirited children especially really need those markers to help them shift gears. They are always on GO so it is important to give them plenty of time to know that they are changing direction. Make sense?
If you're spirited too it may be hard for you to institute a ritual before sleep periods. The spirited adults I know tend to be pretty spontaneous and not too fond of being bound to any sort of a routine. But let me tell you, having a sleep ritual is essential for children. They can't tell time, so it's the only way they have to predict what comes next. Even fly-by-your-seat Spirited kids feel insecure in a world where they have no clue what's happening next! So coming up with a wind down ritual that works for your kid can be very very helpful! And you'll be surprised at how LO will visibly relax when you start the ritual after you do it for a month or so. It's really amazing; a good ritual can do 50% or more of the work necessary to get a child to sleep!
Now for nap timing: it's very possible you needed to shorten A time to get out of an OT sleep cycle. That's my favorite solution for sure! But once he got out of the OT cycle he may have been ready to stretch again, plus LOs this age increase A time about every 4-6 weeks. So enough time may have passed that it's time to increase. But let's do it slowly so you don't get into another OT cycle.
The reason that I kept your nap at 1 pm initially is because I'm gonig on the assumption you're still going to get a short nap. With only 30 minutes of sleep under his belt, he's just not going to be able to handle a full 4 hours. Try 3 hours first. If that doesn't work, increase the space between the 2 naps until you get to where that PM nap is a nice length.
What typically happens during the 2-1 switch is that AM nap is kept short (30-45 minutes) in order to preserve the length of the PM nap; at this age, they can really start to lose the ability to sleep in the PM if they sleep more than 45 minutes in the morning. So, you end up with a consistently short AM nap. That means they just aren't going to be able to handle really long A times so the PM nap doesn't change too much in timing -- maybe it will shift by 30-60 minutes or so. Yes, bedtime may become later briefly, but then once you go to 1 nap consistently bedtime will become earlier. You're probably going to see your bedtime move around a bit over the next 6 months, and then it will stay in one place for 6-12 months.
the main thing to remember during the 2-1 switch is to honor your child's A time. IN other words, don't worry about the clock -- just pay attention to what A time works for your kid and make sure that is how you time naps and bedtiem. That will be your best insurance against OT.
Does this help?