All British men who were not in mobile units and who otherwise were considered "marching units" were provided with motor transport.
Staff in Athens were doing advanced planning for a withdrawal of all British forces from Greece. As early as 13 General Wilson's staff told the naval staff that the army would soon begin to withdraw their forces from Greece. The naval staff were informed that the withdrawal could begin as soon as 15 April.
In Egypt, General Wavell's staff did preliminary planning for a withdrawal. Around the time that General Wilson's withdrawal order was sent, the Germans had achieved virtual air control over the forward areas
The Germans made a dawn attack on airfields in the Larisa area and were able to destroy ten British Blenheim bombers on the ground. The British air commander witnessed the artack and ordered the surviving aircraft be flown to Athens After their success, the Germans bombed the Larisa air field durin the day.
The Germans also bombed Elasson, site of General Blamey's headquarters. British troopa loar their air support and only saw German aircraft in action. British aircraft had been operating effectively, often wthout their soldiers seeing them in action.
During this period, Greek unts were able to hold the Germans in the "Pisoderion and Klisoura Passes. The "Western Macedonian Army moved into the Venetikos Position. It had "been about noon on 14 April when the 20th Greek Division had been driven out of the Klisoura Pass". This is based on the account in "Greece, Crete, and Syria" by Gavin Long.