The WC Code is retrieved during time entry and processing payroll will not update the WC Code or State with any changes made on the employee settings or the WC tables (rates will change but not the code or state).

Changing the WC Code on the Employee setup or on the Cost Code WC Table will not automatically refresh the WC Code on previously entered time entry lines.

If the wrong WC code is on time entries, you will either need to manually enter the new code using Change Unposted Time, or enter the new code in Enter Checks by selecting Detail each line of time and updating the WC Code and WC State by,

NOTE: If check is Printed, the check will need to be voided and either retained as new and follow the steps to update the line of time in enter checks or not retain as new and re-enter the check from the beginning

See linked article DocLink: How are the WC State and WC Code retrieved during time entry in payroll? for information on how the information is retrieved.