Unternehmen Herbstnebel ("Operation Autumn Mist") was an offensive planned by German Field Marshal Walter Model and his Army Group B operational staff in late 1944 during World War II. It envisaged a German Army attack targeting the Allied forces in eastern Belgium and Luxembourg, east of the Meuse River.
"Operation Autumn Mist" actually occurred in late 1944.
The system only knows it was planned an not if it carried out.