The Bering Strait crossing happened more than once as well. The main impediment is that a lot of “my professor said it, I believe it” is from landlubbers who like stuff cut and dried.
When I had my DNA done it said, “<1 Native American”. Turned out to come from my archaic Siberian roots, IOW, common ancestry with people who later crossed the Bering Strait. :^) The remaining descendants occur in eastern Canada, because a group that came in later pushed them across the continent.
I meant to ping you on post 24.