ROSTERkey enables you to set active periods for workers. Specifically, this is designed to remove a worker from the Roster views when they are no longer employed. Similarly, it can be used for temporary periods of absence from the roster.
To manage active periods for an employee use the Configuration -> Worker Settings page.
You can edit the From and To dates of an active period as well as add new periods or remove old ones. There must be at least one full day between any active period and the next, e.g. when one period ends on 1-Dec-2019, then the next active period can start no earlier than 3-Dec-2019.
When a new user is created on Configuration -> User page and their "Worker" flag is ticked, an active period will automatically be created. It will have a From date set from the "Editable From" date in the Configuration -> Settings page and an open To date.