If you click on the menu item Planning, a window opens with two tabs: "Expiring Contracts" and "Future Employments".
Under the tab Expiring contracts, you have an overview over all expiring contracts in your company.
With the function "list of candidates for this position", you get a list of possible employees for this position. The employees with a green dot are suitable for this position. The ones with a red point rather less.
Under future employments, you can see employees who will assume a position in your company in the near future.
By clicking on the gear wheel, you can also fill the position with another employee.