The "Project People Cost" will use the "Total hours" for the calculation.
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Total hours will always use actuals where provided, but if any actuals are missing it will use scheduled date.

You should be able to quick verify this by check if Total Hours and Actual Total hours match up for the YTD (or period) figures that you are looking at.

In summary for reporting, any future assignments will be based on scheduled hours but any past assignments will use actuals -- if we have no actual data for date, we use the scheduled data until it is filled out.
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