When an employee becomes skilled in a new job (Role) you should add this new Role to their list of competent Roles. To do this, use the "Operator Details" either from the main menu screen or click their name in the Roster Administration screen.
If you come from the main menu page you will have to select which worker you want to add the Role to.
Then click the "+" button near the lower left. This will show a popup window to manage the employee's Roles. Click the "+" on this page to get a new row in the grid.
For the new row, select the new Role for the employee and add the date From which they became competent in this new Role. You can set a To date or enter "n-a" if they have no end for the competency. Click the "Apply" button to save the change.