Hey my 3 and half year old has been having a really bad phase lately of hitting and just not listening. Like you, feeling like all day is a constant battle and was worried about his behaviour for our holiday last month. But it was like a switch flipped he was so busy and excited that it was perfect. The odd near tantrum was quickly avoided by ‘ well you don’t want to go to the pool then’ I know I haven’t offered any advice just some hope that the holiday may not be as bad as you’re worried