The Persians added 82 years to their timeline and tried to make up for some of that by removing 26 years from the NB kings. When the timeline is corrected, the 1st of Cyrus falls in 455 BCE and thus the Exodus, 19 jubilees earlier falls in 1386 BCE. This means 1975, 6000 years after man's creation is 127 years too early. So the end of 6000 years is probably 2131 based on Adam being 30 years old rather than 1 year old when Eve is created.
But if you allow 20 years for Satan's last test of post-millennial mankind and 100 years for Judgment Day, you have to subtract 120 years from 2131 to get a guesstimate when Armageddon might occur.
1975 + 29 = 2004
2004 + 127 = 2131
20 years for Satan's last test + Judgment Day, 100 years = 120
2131 - 120 = 2011 AD.
The 2nd coming occurred December 25, 1992.
If a "short while" is just 20 years, it expires on December 25, 2012.
So? Sometime between 2011 and 2012?
This is not definite, but this would be the closest we get to a 6000-year calculation in relation to the Biblical timeline.
We're told to be alert and awake, so all things must be considered.
God says he would tell his prophets before he does a single thing, so there are some claiming to be his prophets saying May 21 is "judgment day." That qualifies, say on Judgment Day, as a "legal warning."
The Bible says after the UN takes over and destroys BTG (Federal Reserve, CIA, etc) that it will rule for 15 months ("a time and a season"). Still enough time to begin the millennium on December 21, 2012 if things gets started by May 21, 2011.
Let's hope so.