It’s an interesting story, that I find amazing, what was it like to be living off the coast of Wales 9000 years ago..
How did the people get there ??
Why were the people there ??
How long had the people been there ??
How long did the people stay there before leaving or getting wiped out ??
How did the rabbits get there?.....................
“How did the people get there ??”
They walked.
Geologist have found evidence of a land bridge from Europe to UK, from Russia to North America and from Asia to Japan.
They have also found evidence of vineyards in the UK and river beds in the Sahara.
These were Neolithic Europeans - the same who built stonehenge. They had probably been there a few thousand years earlier and were related to both modern day English/Welsh folks and to the Basque peoples.
They weren’t “Celts” - Indo-Europeans hadn’t even emerged 9000 years ago and were probably part of a group that became Hurrian, Finno-Ugric etc. (that latter is my guess).
The people are most likely still there - i.e. their descendants are still there. They progressively became Celticized, Anglicized etc. etc.