Really depends on how much you trust human memory and on what you can “find” on the ground.
I like Adam’s place, 75,000-200,000 years ago, just the right position for a Diaspora from the S.E. Asian archipelago, and there be gold there.
If like me you see a focus on lifting ancient artefacts, especially “written” artefacts, from Baghdad as a primary aim of the Iraq invasion 2003, think of it as Kelly’s Heroes without the nice outcome, you’ll know that more is known about our where froms and whys than we’ll get from prescribed education. The proscribed is always far more illuminating. One of the aims of the current oppressive “outlawing” of questions is to stop our inquisitive nature into deeper happenings I believe.
Anyway how far back?
I love this kind of stuff, tucked away in sites of high strangeness.