I can't find this anywhere on Google, so I'm a little concerned.

My sites have classifieds, and one category we've always had a section for Guns / Hunting. This was never an issue for Google until last year, at which time we removed Adsense from that category.

But every once in awhile I'll get a Policy Violation, anyway, usually when a user has posted a gun in the wrong category (a common mistake is when they want to trade a gun for something else, and they post it in the category for that something else). This is rarely a big deal; Google now just restricts ads to that page, I move the ad, and it's all good in a day or so.

I had such a Policy Violation yesterday, though, and submitted it for manual review because there was nothing there. Today I received confirmation that there were no violations and ads would be restored, but then I saw this sentence at the bottom:

Ad serving will be restored on this page and your monthly review limit will be credited.

Umm... monthly review limit? This is news to me! What is the limit, and what happens if I go over that limit?