The wording in the NAA file (NAA: A446 A1980/723 p.146) doesn't actually mention London, it says "17 Hampden Street, 4 Paddington (England)" which is why I searched for other addresses in England. The use of the number 4 is not usual for Australian addresses but I think it may be for English addresses, I'm not sure though and others may have more knowledge in this area. Also the other false address used for Bernard DUPONT at the same time in Belgium, I know we can't presume anything with this guy but altogether I think its more plausable it is in England than Australia.