You can now display only patients that have no future appointment on the calendar.
This is a simple toggle option under Calendar Settings on the left hand sidebar.
When this is turned on, only appointments whereby the patient does not have a future appointment (as of the current day) will display, and all others will be hidden. To display all appointments, simply toggle it back off.
This setting is not persistent, that is if the page is reloaded it will revert to showing all appointments. This is to prevent any confusion if someone accidentally clicks the toggle and is unable to see their full calendar of appointments.