Matt,
I agree that inactive mods should be removed, and 90 days is enough time to post.
Some stocks however are inactive and there are no posts at all during the silent period. The mod may be monitoring it actively and have it in his favorites, but just nothing going on presently.
Therefore, I think you should consider having the script send a PM reminder to mods a couple weeks before they are purged.
AN
Fee! Fie! Foe! Fum!
I smell the blood of an Englishman.
Be he 'live, or be he dead,
I'll grind his bones to make my bread.