Thanks Alex
Well it is very puzzling, since Shores is clearly not someone who invents things!
So all aircraft stayed longer than I thought. (I was fooled by the wordings on page 75 in Vol 1 Bloody Shamble - I read it some 20 years ago...

)
So we have to find out why Shores is so certain these six aircraft were in Singapore with surroundings between Dec 5th to Dec 19th 1941 when the record cards seems so indifferent.
In the meantime I checked the first aircraft and AB Beaufort file says
T9540 TOC 22.1.1942 1 AD to RAAF 25.2.1942
RAAF record card says : 3.9.1941 allotted 1 AD; 21.12.1941 allotted A.P.C.
This means (to me

)
While issued to 1 Aircraft Depot the aircraft went to Singapore and back again. Looks like it departed back to Oz earlier than the other five in fact.
Now if 1 AD was a British unit it fits with the British record card as published by AB (THAT record card probably contains a lot more details not bothered about by AB - unfortunately...)
The Australian record card goes on with an allocation to something called 100 Sq (TF) which grows out of something they just call O.T.U. (T.F. = Training Flight?, O.T.U = Operational Training Unit). However what is interesting is the date the RAAF card gives for 'received 100 Sq (TF)' which is 22.1.1942. This finally corresponds to the British card TOC 22.1.1942.
Why 100 Sq (T.F.)? Well I suppose the unit was made up of the six Beaufort crews who had once been part of the "real" 100 Sq in Singapore and possibly everyone thought it was a good name and finally a new RAAF 100 Sq grew out of that unit. It seems in Britain this is unknown (or at least not very well known) and has been disregarded ever since.
I will check the other RAAF cards for the remaining five aircraft tomorrow to see if my theories above fits or not. Too tired right now....
Cheers
Stig