According to the live blog: God's will to be completed by the end of the millennium. Very casually said by Louche (;-))
I think this is one of those things that is supposed to rile up the r&f. I mean, we had the same predictions last millenium (the end was going to come by Y2K). Except the end of 'this' millenium is another 80-something years away. This gives them a LOT of leeway, another 3-4 "real" generations and by then a number of new prediction and more new (gas)light(ing). But the end is ~80 years away, what is the urgency?