Clicking Accept <version> Update & Terms records on the account that this version has been accepted, together with which user accepted it and when, and returns you to the page you were on. The banner then disappears for everyone on the account (acceptance is per account, not per user). You need an admin role to accept. The banner's 7-day wording is a policy statement; in the current version the acceptance itself is simply recorded when you click – there is no automatic lockout timer in the code.