It's a long time since I had one that age but we clearly noticed when the kids had an upgrade and behaviour changed. I'd put it down to him enjoying his new capabilities and being to excited to sleep. Don't think it's a problem, just roll with it, it's not as if it's a toy you can take away!

Have fun, it doesn't get much easier, but it does get different.

Our guys get rambunctious and grumpy during upgrades. Their sleep stays the same, but they cooperate less.

It was most noticeable when our older guy got reading. In the space of a few weeks he went from haltingly sounding out words, to (hesitantly) reading strings of words. Maybe it wasn't that dramatic, but I remember it that way. It was late winter and around the same time he decided he didn't want to wear winter jackets/mitts and he didn't like food we prepared for him.

I didn't really correlate the two until after.