General O'Connor decided to do a feint to the west and northwest

After the disappointment of the Italians at Derna escaping, General O'Connor decided that with the forces at his disposal, he could send the 6th Australian Division against Derna to see if the Italians would believe that the general thrust of the offensive would be towards the the west and northwest. The British believe that the Italian 60th Division, with 6,500 troops, was still in the Derna area. The real line of advance was to be across the desert to the southwest, to seal off the Italian escape route. The British were just not ready for that, until almost mid-February. The Australian 17th and 19th Brigades would take Derna, the 16th Brigade would move into Mechili, and the 7th Armoured Division would head for the coast road, "south of Benghazi". This is based on the account in To Benghazi, by Gavin Long.