-- that is your problem to resolve not mine
I think its more of a problem for yourself and all JWS particularly the JWS leaders , most bible scholars and ancient historians agree with the time of Jerusalem's destruction being between 586 to 587.
The problem rests in how to dissolve the doctrine of 607 BCE and 1914 and keep or retain the delusion that the organization is god's chosen and the organization is the FDSL and not commercialized false prophets.
False doctrines and teachings dont complement the proclamation that Jehovah has chosen the JWS organization as his earthly arrangement.
The GB already have stated that the early BS were overly speculating in anticipation to the time surrounding 1914 .
So I think they will soon attempt to make the 1914 doctrine fade away quietly.