stores. The transport engaged in stocking the forward bases alone consumed per day. Robertson developed the concept of the Field Maintenance Centre (FMC) for the support of fast-moving mobile operations. An FMC was like a military shopping centre, supplying all the needs of a corps, and dramatically reduced the response time to administrative needs of front line units and reduced the amount of paperwork that they needed to do to get their needs fulfilled. The FMC would later become a feature of war in the desert, and later British logistics in the Normandy Campaign. The offensive was launched on 18 November. While the Germans were taken by surprise, they soon recovered, and pushed the Eighth Army back. On 24 November, the Afrika Korps threatened the railhead at Mischeifa and the Eighth Army's Rear HQ, which Robertson was ordered to defend. Fortunately for him, the Afrika Korps changed direction. But although the tactical situation was poor, the administrative situation remained good, and this influenced Auchinleck to continue the battle. Auchinleck relieved Cunningham of his command, and replaced him with Lieutenant-General Neil Ritchie. The Germans and Italians fell back in December. To support the advance, the ports in Libya needed to be developed. Robertson went to Tobruk on 13 January to investigate increasing its capacity. He concluded that the problem was the poor layout of the depots, and recommended that they be reorganised. Benghazi was captured on 24 December, and became the key port, being much closer to the front than Tobruk. The logistical challenge was to build up sufficient reserves to be able to deliver an attack on the German and Italian positions around El Agheila. On 21 January 1942, the Germans and Italians struck back. Benghazi was abandoned, and the Eighth Army fell back on Gazala. Tobruk was now the main port, but Miller and Robertson considered it too far forward to stock with more than a week's supplies. They were overridden by Auchinleck, who wanted it stocked for a renewed offensive. But the Eighth Army lost the Battle of Gazala, which began on 26 May. On 2 June, Miller became the Eighth Army's Brigadier, General Staff (BGS), and Robertson took his place as DA&QMG, with the rank of brigadier once more. When Tobruk fell on 22 June, 3,000,000 rations, of ammunition and of petrol, oil and lubricants (POL) were lost. Following another defeat in the Battle of Mersa Matruh,