A quick check of the relevant dates involved means that it's physically impossible for the (currently nameless) maid/housekeeper involved in Doctor Who's Interspecies Victorian Lesbian Crime Fighting Duo (or IVLCFD for short) to be a younger version of Mrs. Hudson from before she came to own the flats that Holmes & Watson eventually meet/live in, because Mrs. Hudson lets her flat out to watson the year before Jack the Ripper was stalking the streets of whitechapel.

But it was such good fanon! Poot.

( cut for spoilers from When a Good Man does something... that new Who Episode )

(though everyone who's incorporating that twist into canon to explain past behaviour of various characters, you are all awesome and your proofs seem sound)