The table orgCalendarSchedule has the patch scan and update schedules for each machine
If you looking for the updates only then filter on " where ref like 'de7%' and agentguid = 1234567" etc
This will return just the update schedule for the given agent
So if you are OK in SQL , create a view of your own and then you can reference the view via a getvariable , or use the new SQLRead function to query the view
So with the info in the view you should be able to work out based on the schedule and the current date/time when the next one is due
Paul