VaMX is updated to the latest version of Virt-a-Mate. VaMX receives updates to the latest version of the vamX plugin (where new features are constantly added) every 6 months. It arrives in a single Mega Update (with more testing the normal monthly updates) with all vamX VIP features (which are normally $10 per month). So the itch.io version is updated infrequently, but updates are free forever (instead of paying $10/month for the vamX Patreon features). If you are very very eager to get an update, you can pay the $10 one time to update ahead of schedule.