Slimboy's point is correct according to my reading of the paper which there is a Link to in the Article.
So, yes, we cannot say the Scientists that did this have proved beyond doubt that Aviv in 586BCE was the date for Jerusalem's destruction, but by looking at the other events that are dated without doubt and working them from 539 BCE if you want to do that, then the 586BCE date is not far out, it could be a few months at most, but had there been a disparity of much more than that the Scientists would have been alerted and checked it out.
I am surprised they used the Aviv 586BCE date as an anchor merely accepting it as spot on from the Hebrew Bible, but as I say, no BIG discrepancy in that can be calculated however you try to do it.