Let's say I have a provider-hosted app that's installed on a client's Office 365 site. A user clicks the app and they're redirected to our site.
The redirects gives us (among other things) a Refresh Token, so we can continue to make requests on the user's behalf, bound by their user permissions. All is well.
However, the Refresh Token expires after 6 months. How do we get another Refresh Token before this happens? Do we get a new token if they visit again before the expiry?