No doubt 3.5 years. We used to have a 6 pointer that we would see regularly that was young like this buck but was a legit 20" wide buck. He would walk out, I would get all excited rapidly throw up binoculars, only to realize it was the same damn 6 as usual.
Why didn't I shoot him as a cull? We had a minimum 8 point in addition to minimum 4.5 age before we could take a cull. No this was not a BradMitchJerry place. Believe it or not, rules like this are not uncommon for heavily managed places that regularly produce 160+ bucks.

Anyways I digress. We watched that stupid 6 pointer for years because we could not cull him. He was taken at 6.5 years as a 'trophy' at the end of a season because we would not catch flack due to his age. He ended up being a 20" wide 7 pointer that scored 113.