I have no idea how this is happening now.
I have completely uninstalled Calibre for Windows, including the Roaming folder created for the user.
I then installed the latest version 0.8.4 and when I check the version under Properties it says 0.8.4.
And yet whenever I launch Calibre, even when I click on the 0.8.4 EXE itself, the application launches, shows as 0.7.7 and notifies me that there is an update available.
When I debug devices, the log also states it's 0.7.7.