New Income Category removes tracking of ROE Insurable Hours

I want to add a new income category to pay out Banked Time Used as I am tracking Banked Time earned in a separate spreadsheet. I don't want vacation calculated on this new income as it is over time that is banked.

When I rename the new category, link it to the wages account, and change it to hourly it gives me a warning message when I want to click OK in the setup - settings

"For the income you have modified, your changes will remove the tracking of insurable hours from your employees' ROE forms and payroll records. Do you want to save your changes?"

Why is this warning message coming up? I don't want it to stop tracking insurable hours. Is there a set I am missing?

Thanks for your help.