Necro-bumping (Namely posting in a non-Official/Moderator approved thread 30 days after the most recent post) will be treated as a form of spamming if the post in question has no valid reason for being posted, or treated as a form of flaming/trolling if the post in question is malicious in its intent. It will be up to the Moderator to rule on whether a necro-bumped post is pertinent or not
I think it is a bit silly that you have to ask permission or get an okay for necro bumpin thread because like 95% of the users probably don't know about this rule =p.