Imamura was up against a resourceful, resolute and aggressive opponent, who also had access to good intelligence. Allied Ultra codebreakers were reading the Japanese shipping codes, and, by 3 January 1943, Allied commanders knew in advance about the force that Adachi was planning to send from Rabaul to Lae, although they did not know the force's ultimate destination. Blamey chose not to wait for this to become clear, but immediately ordered the 17th Infantry Brigade to move from Milne Bay to Wau on 4 January 1943. Its commander—Brigadier Murray Moten—was ordered to assume command of Kanga Force and defend Wau.