Glad it’s helpful. It took a fair amount of trouble to figure all this out and I hoped my learning time could be reused for other people.
About decrementing the infringement counter after the ten-day timeout, that’s an issue that’s too subtle for a summary like this. It would be the point where you call your lawyer.
The reason this is subtle is that getting lots of takedown requests for a user might count as “red flag” knowledge, which obligates you to act with or without a takedown request. This could be true even if there are counter-notices and the ten day window expires.
Decrementing the infringement count after the ten-day window expires is a business choice. You want to strike a balance between protecting yourself from lawsuits and creating a good environment for your users.
made with a mature understanding of the legal risk and manual examination of the account.