1.  The lengths of the trunk road described in an item in column 2 of the Schedule to this Order and given the reference letters A, B, C and D in column 3 of that Schedule and shown by broad striped hatching on the deposited plan shall as from the date on which the Secretary of State for Transport notifies the Council whose name is specified in that item in column 4 of that Schedule that the new motorway from Umberslade to Warwick is open for through traffic cease to be trunk road and be classified as principal road.