A.S.
We've gone through several phases like this with our son, and I don't pretend to have all the answers at all - in fact we still regularly struggle. But, one thing I've figured out, is that its a fine line between him not being tired enough to go to sleep and fighting it, or being over-tired, so he's pumped up on adrenaline and physically can't get to sleep (the fidgeting sounds like the latter). Its like if you go for a run or do other exercise late in the evening - its much harder to wind down straight away for an early bedtime.
We've found that the most important thing is for ALL of us to be relaxed at bedtime (especially the adult doing the putting down) so that we can help our son relax. It doesn't mean we can't mess around and tickle and chase etc after coming home from work, but that we need a good wind down period before the story even. Easier said than done when racing around all the time to and from work, and never feeling like we're getting enough done in any domain! It almost seems like our son has an attention 'bank' as well... The more fun quality, playing and on Aidan's agenda time we spend together, the more relaxed and secure he is, and the better he goes to sleep. If we've been away a bit more than usual, or distracted or stressed ourselves during our time with him, it seems to play out at night. I think our son is just particularly sensitive actually, as no one I know has had such a high level of variability as us - although we did move recently, which completely through the good nights/bedtimes off.
I also find our son sleeps better when he's had a good mix of physical activity with plenty of rest as and when he needs it - so that he's not being 'kept up' when he's timed, but he's working hard when he's not tired.
So, for your little guy just be on the watch for that fine line - may be worth a try to cut down to the one nap per day consistently. Previously, he might have been catching up on sleep lost the rest of the time when he was with you... now, he might be more suited to a steady schedule all the week through. Or, he could be simply over-tired most of the time if he still hasn't caught up on enough sleep from that late night a while back. Maybe just see if you can figure out where he stands on the over-tired vs. not tired enough continuum for a bit, and then once you've figure that out, make a few changes and stick with them for abit.
Good luck!