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You can select from "Work time compensations (overtime, extra) according to CBA" menu which overtimes and extras are going to be itemized in the time reports for payroll (Projects > Work time settings > Additional options). From "Overtime additives and other additives compensated as free time" and "Overtime base hours compensated as free time" menus you can select which overtimes and extras will be compensated as free time.
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From "Additional options" in "Work time settings" you can select "The employee can select overtime", which allows employees to set overtime assignments for themselves.
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From "Other settings" menu, you can select the project work time decomposition setting to override possible employee work time decomposition settings.
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Employee level overtime settings
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