Add user Shift Hours, Vacation scheuldes, and Events via API

We're looking to integrate the shift hours, vacation schedules, and events sections on the user profile pages with our HR and calendaring systems, but cannot find any reference for modifying these fields/tables via the API. Is this something that can be done?

This would allow us to automatically populate employee schedules and availability onto the dispatch board, to prevent work from being scheduled while a staff member is busy with a non-corrigo task.