Cindi Foreman, of Ottawa, Canada.
A huge congratulations to Cindi, who gave the closest answer to my question:
How many “4th Cousins or Closer” I have according to Ancestry’s DNA database on 21 December 2019?
The answer in this case was not 42, but

Given the numbers that were guessed, I’m starting to think I’m rather lucky having such a low number and that I should be more focused on looking into them all, rather than feeling overwhelmed by the figure!
Thank you to everyone who entered. There are still some competitions still open, you can find these over at Life in the Past Lane or on the Conference Keeper.
I’m looking forward to seeing you all in Salt Lake City.
Please note: As an Ambassador I receive a complimentary pass to the conference, invites to some special events and a free pass to give to a competition winner. However, all the views expressed are my own. I pay my own travel, accommodation and spends whilst I’m out there (which include, but are not limited to a new pair of Converse and probably some jewellery!)