My eldest was like this when he was that age and my youngest is behaving the same way now.

I found that they needed extra stimulation as daycare wasn't providing enough and they were/are ready for school. It is like they are pushing boundaries because they are bored and deliberately getting me angry/annoyed was an interesting pay off for them.

For my eldest, as soon as he started school, he went back to his normal self as he had new experiences to explore. For my youngest, he starts school next year so I have to ride it out. I have spoken to his carers and they said they often get the kids who are starting school the next year behaving this way for the last 4-6 months before the move up.