Gosh -a few options
a) They'll choose a not too close/distant date and submit suspect calculations as to how they got there - and 90% of Dubs will swallow it.
b) They'll start at 1914 and keep adding various WT numbers to it -so the Dubs can make a valid connection.
c) The New Light (tm) will be 2034 as the START date (1914+120), which will give them plenty of thinking time.
d) They will use the 'generation' of 1914 (which is so predominant it would be fatal to ditch it) to manipulate further what a 'generation' is.