I am still not getting how I got banned for herbing 4 - 5 hours in the past 3 days and the last day was a 3 hour harvest.
IMHO, there is no way Bliz would perma-ban automatically. It would require an investigation of some sort from a human.
If the premise is true, then the behavior for which you were banned did not occur in the past few days, but probably in the past six to eight weeks or more. The action was just delayed due to normal 'Bliz delaying tactics', or it took that long for their team member to reach the final conclusion.
Your "herbing 4-5 hours in the past 3 days" was certainly not the cause of the ban. Instead, it was some previous detectable unsafe botting practices. It could have been something as simple as a profile that Blizzard keeps an eye out for. For example, profiles that grind for Volatile Air in Uldum seem to be watched heavily, or reported a lot by the player base. Rainspeaker Rapids in Sholazar Basin was another such area because of its constant generation of mobs that allowed rapid leveling just by grinding. And botter popularity made certain areas of Zul'drak a 'likely to ban' area.
As another example, I ran a profile the other day that spammed the same macro 200 times over the course of 90 seconds. This type of action is a ban waiting to happen. I let the profile continue because the damage had already been done. Silly me thought that would be the only instance of it in the profile. Then, I saw it do the same thing again later on. At that point I dropped the profile and will probably never use it again. Over-use of the
RunMacro behavior in a profile is a major "no no", as its how a number of other bots have been identified and ban-waved. What this profile did was outright
RunMacro abuse that is even warned about in a highlighted "Things to Know"
on the Wiki page. It might have well just added "/yell I'm a bot" while it ran, as the damage couldn't have been any worse.
Although I try to practice 'safe botting', I allowed a profile to conduct unsafe botting practices on my behalf. The failure was mine for failing to check the profile before running it because I blindly trusted the authors.
In short, there could be a lot of ways you got tagged--all server-side detection. Its not very likely your recent herbing practices were the cause.
cheers & sorry for the loss,
chinajade