National Minimum Wage tick box

On the employee tab, pay options tab is a tick box for NMW which when ticked will apply the relevant NMW to that employee. If this box is not tickedt, when the employee moves into a different age bracket for NMW this is not picked up by payroll meaning that they could end up being paid less than NMW. We have employees who are paid above NMW so it would be useful if the tick box could be selected AND be able to manually change the pay rate so that it doesn't revert to NMW.