I finally managed to track down what caused this, it seemed that it was coming from another script I’ve made a while ago which was simply starting prop movers that were assigned to hover platforms.
Just in case someone from the staff comes here, the hover platforms I used was the ones with the blue fire under them, I think the problem is that those platforms have some children components that are set to static.
I actually got a warning in my logger but wouldn’t think it would impact the server tickrate so much.
I replaced them with HoverPlatform that have no static children component and it seem to work! Really strange though…