Like /u/MeatballDom points out, history moves more through Kuhnian shifts than Popperian revolutions. With that said, I think we're getting some exciting evidence that is pushing back the timeline of settlement in the Americas and if the evidence pans out and we find more, it could be a big shift.

Also, with new technologies like Lidar we're finding out more about settlement patterns and urbanization. It sees that we had underestimated the size of population centers throughout the Americas. Combined with the earlier settlement info, we might very well increase estimates of the populations of the Americas at the time of settlement from about 40ish million, which is kind of the standard right now, to one of the higher end estimate ranges.

But it's not a sudden shift. People have been arguing this for decades and slowly building and examining an evidentiary record for these theories.