From "Action Stations - Overseas":
"Two of the first RAF units to be based at the airport (Kallang) were 11 and 39 Sqns, both flying Blenheim Is, which were sent from India to reinforce the Far East Command in September 1939............
"Early in the following year (1940), Kallang became a fighter base when 67 and 243 Sqns both reformed here with Brewster Buffalos...........
"At the end of the Pacific war it was, purely by chance, at Kallang that the first British personnel set foot in Singapore. On the morning of 31 August 1945, some days before the actual signing of the Japanese surrender document, a
PR Mosquito of 684 Sqn (landed at Kallang with engine trouble). The crew received a friendly reception from the Japanese who produced RAF engineers to effect the necessary repairs......
"The first administrative body to move in formally after the war was 903 Wing (part of HQ 224 Group) which in effect formed RAF Kallang. No 31 Sqn arrived from Burma with its Dakotas in September, 1945.........
"The RAF, for its part, decided to hand over its interests at Kallang to the Singapore Government and to concentrate its transport aircraft operations at Changi (in 1955).....
Hope that helps.