 Final preparations for the landings in the Brunei Bay area took place in May 1945 . After shortages of shipping delayed I Corps ' movement from Australia to Morotai , General Headquarters agreed on 8 May to reschedule the operation from 23 May to 10 June . The 9th Division 's staff completed their plans for operations in the Brunei Bay area on 16 May . The 24th Brigade Group was assigned responsibility for capturing Labuan , and the 20th Brigade Group was tasked with securing Brunei and Muara Island . Both brigades were to land simultaneously on the morning of 10 June . The invasion of the Brunei Bay region was to be preceded by attacks on Japanese bases and transport infrastructure across western and northern Borneo by United States and Australian air units , as well as three days of minesweeping operations in the bay itself . 
