Is it against app store policy to release a free app, then lock it down after 30 days (or some other time period) if they don't pay (purchase an in app payment

Is it against app store policy to release a free app, then lock it down after 30 days (or some other time period) if they don't pay (purchase an in app payment or subscription)? That is a traditional "free trial" approach, but I don't think apple even let's you do it.