So all 3 are mad chewers since the op? That’s interesting… It could be still bunny teenagers. (I looked back at you last post – you said the pair is 8 months?) How old is the third? They are all in the same household now?
I’m not sure if it could still be related to hormones but they do take a little while to completly leave the system. Chewing is a form of play and good for rabbits to do but it can be destructive! Try providing lots or alternatives to chew. Willow baskets or sticks, a “hay bungalow”, apple wood, sea grass mats & HAY, HAY, HAY!! Do they get unlimited hay? I find my rabbits go to town chewing things that are “stationary” that is they can really tear at something and it doesn’t move about like chew toys can do.
How do they seem otherwise?
I just found this Q&A that is a little similar – regarding 8 month old rabbit just spayed. Maybe that might give bit of a clue to what’s going on.
en.allexperts.com/q/Rabbits-703/Spayed-rabbit.htm