This reminds me of a Time Team special where they pointed out that the island of Great Britain has completely lost its human population and be re-populated at least seven times so far.
I wonder if the word finally is misplaced there. During the next glacial period, the area may become uninhabitable again. In those past 700k years they talk about, there may have been periods much longer than 12k years that the area was inhabited. Each of those previous 7 settlement attempts would probably have seemed like the finally successful attempt to the people at the time.