He is transforming into a very much regular child, albeit on his own schedule. If I had to describe it in one sentence, it feels like he is 2 years behind the schedule, exactly. He's 7.5 now and the slow transformation has been happening in the last 1.5 years. Less and less problematic (toddler-like) behavior in stores. More increased capability to listen to the reason. To the itinerary of our trips. Increased ability to self-reflect and see his own behavior (instead of blaming everything on everybody else). It feels now that we are out of toddlerhood and I have a perfectly capable 5yo...... In the great scheme of things, being 2 years behind (some) schedule is not a big deal.
When he was 3 in pre-school, he was more like around 1.5-2yo, and eventually pulled out. (Now looking back I see that, but at the time I was expecting a 3 yo behavior from him, and it was frustrating). When he went to school at 5, he had exactly a 3yo inability to listen and focus. He was dxd with high-functioning autism at 4.9, with some areas above and some below the norm. He had some accommodations at school (a few kids with a couple of teachers) which was great at the time - as it would be for a 3-4 years old. But it started to feel limiting as he grew more able but the school format was not willing to change. Honestly, reading articles online helped me a lot.
In short, I have a very able and intelligent little guy here with an ability for math and an uncanny sense of people and their inner desires. I think boys in general can be a bit slow in early development, and we in particular fell into the trap of finding a syndrome, when there was not much to worry about - all that needed was patience.