Setting for Labour role on timesheet only changes billable rate

When add a labour role to a timesheet could there be a setting so this only changes the timecards billable rate and therefore costs will only come from the employess HR settings.

When someone can be billed out as different roles doesn't mean their cost would change and this should come from HR.

Screenshot is extreme example of incorrect cost from Labour Role

Situation is a Foreman who costs more than a Labourer has to work for a day as a Labourer and can only be billed out at the Labourer rate. Problem then is they are still paid at Foreman rates but by selecting a Role the cost changes to the role cost not the employee HR cost.

Also works the other way where you may have a skilled worker that sometimes can be charged out as a Designer vs Project Manager vs Estimator which are all at different bill rates but the cost is the same as they don't get paid differently per role.

The only way to get this working so costs are correct per employee is to setup various labour roles for specific individuals per project which is time consuming and easy to select an incorrect role