If you go to Home » Administration » Structure » Content types. Choose Basic page, then the display settings tab. There is a checkbox "Display author and date information." that says "Author username and publish date will be displayed.". I would expect that with that checked it would show the date/time of the current revision published. But it is instead showing the date/time of the last revision created. I would not want to show Anonymous users a date/time for a revision of the page that they have no access to. It would be better just to show them the date/time of current revision (published).