The JW's don't need to know anything, they just receive the order from "Mother" and follow it through. Many though will probably just dump them and pick a number to report. The BS of the end is near is getting so damn old already, when will people realize that the stuff that is written in the bible about the end referred to the end of that particular system which happened in 70 AD? WAKE UP PEOPLE, do some research on history and how many times christians have thought the "the end was nigh" it has happened many times before, read about the plague for example or the many wars and genocides that happened hundreds of years ago, there is no difference, only that now we have alot more people on earth and the media to tell us about any little disaster that happens anywhere, and this is just feeding the monster of "The End is Near" mentality.
A book that I highly recommend is "End-Time Visions, The Road to Armaggedon?" by Richard Abanes, that book helped me see that this belief is not based on reality, just a slogan to scare the flock into submission.