Oracle HRMS does not permit you to assign employees to structures on dates earlier than their Date From, or later than their Date To. Similarly, the system protects you from building eligibility rules for compensation and benefits based on work structures that have not yet gone into effect, or are out of date.
Suggestion: Consider using a fixed date, such as 01-JAN-1901 as the start date for all your initial work structures. By choosing a date like this you can immediately identify all of your implementation definitions. You should use accurate dates for all subsequent definitions.
You maintain both dates and version numbers for these hierarchies, to keep a history of your hierarchies as they change over time.
To build a new version of a hierarchy, you can copy an existing one and make the necessary changes to it. When you save the new version the system automatically gives the previous version an end date.