Therefore, its known narrative elements are not a part of the Doctor Who universe. It may have been the basis for a similar story in another medium, however — and that story may indeed be a part of the DWU.
The Children of January was to be the last story of the original Season 23; when work on the season was aborted following the near-cancellation of Doctor Who, the script for this story was scrapped along with all the other proposed stories. The Children of January remains one of the few 'lost' stories from the Sixth Doctor's era to have not been adapted, either into a novelisation or into a Big Finish audio adventure.
I wrote a two-parter called The Children of January. It was to be a season closer, not a series termination. But the BBC decided in mid-season that the show had run its course and, in the middle eighties, I think they were right. But I loved my episode, which was delivered late in 1985. I created a race of runaway proto-humans called the Z'ros, sort of 'human bees', of which I still have the fondest nightmares. 'The Children of January', incidentally, refers to renegade outcasts of a dawning "parallel universe" civilisation that was abandoned.