If he is a truly mature buck then his basic frame probably will stay the same but he may grow in mass, width, tine length or add some nontypical points(kickers, drops, forked brows, etc). Liked mentioned other factors are invloved with the year's antler growth.

farmcntry, is your Taxi on crack??? I am sorry but a 4 1/2 year old deer is over the hill...ummmm I don't think so, more like prime. It does sound like a older animal and possibly a downslider but I would question him again on the age...cuz what he is saying just don't add up to me.