Kitten calming methods?

My kitten, felix (6mths) is getting neutered on Tuesday and boy I can’t wait. I love him, beyond words but he’s starting to push my buttons. He’s starting to get very aggressive and naughty. I’m honestly hoping this neutering will calm him right down.

He’s a very active kitten, always on the go. I normally don’t mind this, I play with him for hours & he’s a cuddly boy. But recently, he’s been a twat. Especially in the nights. For example, it’s currently 1am and he’s been playing up since 9pm. He’s only now just settling. He cries if he’s locked out and if i leave the door open, he will pounce, attack my face and bite me until I wake up.

I’ve heard about FeliWay, a calming plug in. But i’m wondering if it’ll help him with how active he is & how naughty he can be? I’m going away in a month and wanted to help him with his separation anxiety as well. We live with my grandparents so he’s not going tk be left alone aha!

Any tips on plug ins & how effective they are would be extremely appreciated! Or even if anyone knows what else I can do in the mean time to stop his behaviour.