User IP address change causing session issues, wrong content

Have occasionally had reports of users who are logged in, yet they see cached "Per User" "Per Role" content as though they are not logged in. Logging out and logging back in does not fix the issue, but clearing browser cookies does. If cookies are cleared, the user can then successfully log in again.

One thing I have noticed is every time someone reports this issue, there is a new IP address associated with their account. Users typically do not log out, so they are simply loading the site again when accessing with a different IP address, and Authcache is rendering the content as though the user is not authenticated.