Deselect payroll categories for employees who have used Timesheets

I know this question had been asked over and over for years but still nothing has been added to fix the problem. We need to be able to deselect payroll categories that are no longer required for certain employees. Our business has different categories set for Fulltime employees and Casual employees, we have had multiple employees that have started as Casuals and then moved on to be fulltime, when I enter in the timesheet it comes up with both sets of categories and gets very confusing as the list grows longer to go through and sometimes we accidently end up selecting the wrong category and paying the employee incorrectly, there needs to be an option so that you can make categories that have previously been used in timesheets inactive for certain employees to avoid errors, even if you have to select a date the category become inactive for that employee so that it stays in previous timesheets but for timesheets from that date onwards no longer shows the inactive categories.