The A487 Trunk Road (Caernarfon Flyover Southbound Exit Slip Road, Caernarfon, Gwynedd) (Temporary Prohibition of Vehicles) Order 2018 / Gorchymyn Cefnffordd yr A487 (Ffordd Ymadael tua’r De Trosffordd Caernarfon, Caernarfon, Gwynedd) (Gwahardd Cerbydau Dros Dro) 2018