The success of Megiddo depended on the Turks not retreating in Palestine nor advancing in Syria. A retreat in Palestine of seven to eight miles would have undermined the offensive. The joint NAA and EFF plan was focused on an elaborate deception operation aimed at the very heart of Army Group F’s strategic concept: The need to maintain the Hejaz railway and the belief that the Turks would have sufficient defensive power on the coast to stop or slow an advance.60 During August-September 1918 the EEF and NAA carried out the following coordinated deception operations: