I would appreciate views on how to manage this situation:
Additional Info and screen shots attached.
Company’s organogram is divided into business units. Each business unit has its own subaccount. The purpose of this is to be able to allocate employee costs and pull reports according to business units. Each Employee’s set of subaccounts is that of the business unit they belong to.

At times it happens that employees move between business units. This requires that the subaccounts for those employees are changed to those of the new business unit they move to.
One does not want to change an employee’s ID every time the employee moves from one business unit/cost center to another.

Problem:

The following information, entered on the Employees Screen, is not date sensitive

1. 1. Employee Sub-account
   2. Employee Company
   3. Employee timecard approver
   4. Employee Supervisor.

This has major operational and integrity implications when any of the above information pertaining to the employee is changed.