LONDON, n.d. [on or after 9 June 1937]
PART II: DEFENCE AGAINST INVASION 
It is noted from paragraph 22 that the maximum time that must be allowed for the arrival of the fleet at Singapore is 70 days, apart from political factors. In paragraph 24 it is stated that a considerable period may elapse before the progress of our operations against Germany and the re-distribution of our forces permit of a fleet arriving in the Far East.
It would be appreciated if advice could be given as to the estimated time for which it is anticipated the Singapore Base could resist capture at the present stage of its defences, and the period for which it will ultimately be able to hold out when the defences are complete. Advice of the year in which it is hoped to complete the defences would also be of value in estimating the risks which are related to the part of this Base in the scheme of Australian Defence.