This was one of the biggest issues that led me out of the WTS. I spent months researching history for some kind of proof that Jerusalem was destroyed in 607. Needless to say, I got very disillusioned.
The archaeological evidence of 587 is concrete. The Neo-Babylonian dynasty is one of the most well-documented eras in ancient history.
So, I started looking more internnally to see what the WTS has taught on the matter. I read Studies In the Scriptures and other old books and came to realize that the doctrine has evolved dramatically over the last century. The whole chronology thing was adopted from the Adventists when Russell met Nelson Barbour as a young man. They origginnally thought that Jerusalem fell in 606 due to their ignorance of how to use math in the counting of years. 1914 and the Gentile Times was only a small part in the elaborate puzzle of Parrallel Dispensations, which outlined correlating periods of years in biblical times to matching year periods in modern times. The whole plan of God was supposed to be proven by measuring the Great Pyramid. 1914 was supposed to be the furthest limit of the rule of mankind on Earth. When that didnt happen it was later re-interpreted as the start of the last days (which was previously held in 1799).
I also carefully read the Bible to see if it supported the 607 date. It soon became apparent that the WTS had made a drastic mistake in thinking that Jeremiahs 70-year prophecy was foretelling a 70-year desolation of Judah. The Bible strongly indicates that this prophecy relates to a 70-year period of Babylon as a world power, which would allow the historic figure of about 50 years that Jerusalem was uninhabited. I also mailed some Jewish historians who agreed that the Babylonian exile was for about 50 years. The WTS constantly refers to historian Josephus figure of 70 years, but fails to ever mention that Josephus had corrected himself in his last writing down to 50 years. I found that the Bible and established history are in harmony on this account. The WTS teachings cause several blundering inconsistencies with the Bible, among the foremost I noticed was the acount of Gedaliah. I shake my head with disbelief that I followed such faulty doctrine for so long.
After my disfellowshipping, I started reading books by ex-JWs that corroborated my findings. As to be expected, I found I was certainly not the first JW to figure these things out! The most comprehensive book on the subject is Carl Olaf Jonsens' :The Gentile Times Reconsidered. His other book: The Sign Of The Last Days- When? is also excellent. Get these books at http://www.commentarypress.com
Happy reading!
Wayne Rogers