My thoughts on age are that he is just a 1.5 year old buck. His hind quarters are defined and thin. He has a short body. His ears are oval like that of a young buck. Also, look at the pedicels. They scream 1.5 years old. He was probably born really early in the year, had no siblings and got plenty of good food in his life. Genetics are obviously good too. Many things dictate how far along a 1.5 year old buck will be in development. In my bowhunting area, it is quite common for 1.5 year olds to have 8 or more points.
After all, the Hanson buck, the world record whitetail, was only 3.5 years old.
I'm not denigrating you or your buck, just being honest.