EGR cleaning in any manufacturer service schedules?

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As per the title, given the state that EGR valves get in (not surprisingly), does anyone know whether any manufacturer includes cleaning it as part of a service schedule? Or suggests a time interval for doing so? Given that so many report better performance (placebo) with it cleaned (or blanked), surely this would be beneficial or would they rather it fails completely and they can supply a shiny, new one?