Thanks, BOAC. One of the site admins has disabled the option that lets users choose how many posts to view per page, which forces everyone to use the default view. Aside from being easier on the server, that means everyone should be on the same page now in terms of troubleshooting.
If, as you see them, you could link to threads in which you observe the "show more pages than there actually are" issue, that would be helpful. (Please start a new thread, as this one is about time stamp problems.) Thanks!