so basically more than an year is the ideal time which can take upto 2-3 years as well.
I believe that becoming a Hero Member is not a matter of time.
You must know your purpose in the forum. 2-3 or even 4 years will not become a Hero Member if the goal is only to participate in the bounty campaign. I've seen many accounts that have been around for some time on forums with such a purpose. make thousands of post report bounty. without any merit. no matter how much activity and how long they were on the forum, they would not become a Hero Member.
as I recall, there is a thread showing the ranking of newbie accounts having thousands of activities. I forgot where to read it.
What I meant was if I stay active in forum and posts regularly. Will those merits come by itself or will it be send by other members.