Hi there, how are things today? Sorry to hear they were going fairly off for you. No fun
Just re-reading the whole thread now. Sounds to me like the 28 minute WUs are bascially the same thing as the previous 30 minute WUs. Let's say all of that is OT and let's go back to the drawing board. Take him back to 2hr 20 A time (or even a tad shorter if you have a hunch about that - 2 hr 15 maybe?) and try some nap extension techniques.
If he does a short nap, normally he should have a shorter A time. This is not always dramatically shorter (ie he might not go down to, say, an hour's A time) but certainly somewhat shorter, maybe 30 mins or so. Watch his cues.
He stirs very briefly and then seconds later his legs are in the air, he chats, plays with his lovey and if I try to resettle, just laughs at me!
You need to get him at that first stir if you're doing anything like laying hands on, more sh-patting. It really is a matter of seconds. And if you watch you may notice an even earlier cue. I would intervene, very softly and gently, at the first moment of approaching wakefulness. For W2S you need to get to him before his usual WU, so if he wakes at 28, then you need to 'interrupt' him around 20/25 minutes.
For me, I found with both my LOs at this age that the quality of the wind-down and the first 20 minutes of sleep were crucial to how the rest of the nap went. My first LO was touchy so having a really good wind-down paid off. Having done sh-pat on the shoulder, I would keep a bit of sh-pat going very gently as he was in the cot to help him settle and really get into a good sleep. I would sit with him, HTTJ, and then pat if necessary around the 25 minute mark. If we got over that, then the rest of the nap was pretty good, usually. As you say at the beginning of your first post, this is about teaching how to get into a good sleep and how to transition. So if you approach it in that spirit, you'll find the lesson is learned, in a few weeks.
Another good tip is to get him to go down for his naps in his cot (keeping your New Year's Resolution
) and if he wakes, get him up, without much discussion, and into a sling or his buggy or car seat to continue the nap. If this works, then he sandwiches two naps together and you get somewhere around the amount of sleep you hoped for. I used to do this for one nap and sit by the cot for the second nap.
A lot of this is to do with your mama instinct and what you can see your LO doing: so come back and describe how it's going on and we'll see what we can do.
HTH