Her entry in Gaige's Chess Personalia (1987) reads as follows:
Gaige wrote:Finn, Miss Kate Belinda
d 08-03-1932, London ENG
BCM, 1932, p. 167-168
London Times, March 9, 1932, p.1, c.1
Here's her BCM obit in full:
BCM, April 1932, pps 166-167 wrote:Miss K. B. Finn, first British Lady Champion and one of the strongest women players of her day, died of bronchial pneumonia on March 8  at 12 Rugby Mansions, Kensington. She was the only daughter of the late Eugene Finn, M.D., of Patricks Hill, Cork. Her mother, who died in 1906, was fond of chess, encouraged her daughter to play and accompanied her to the various meetings. When the British Chess Federation was formed in 1904 she entered the Ladies’ Championship at Hastings and won with a score of 10½ out of 11, a wonderful performance. In the following year, at Southport, she again won the trophy, but the opposition was keener, her score being 9½. In neither event did she lose a game, the points she dropped being the result of drawn contests. Her mother’s serious illness prevented her from appearing at Shrewsbury in 1906, and as events turned out, she never again competed, but her strength a first-class player was maintained till quite recently, when ill-health and failing eyesight made her appearances more rare. For years she played top board for the original Ladies Chess Club, which then played in the “A” Division of the London League. Here she held her own with the leading London players. Latterly she joined the Imperial Chess Club, and was a regular and valued attendant.
And the Times reference is as follows:
The Times, 9 March 1932 wrote:FINN - On March 8, 1932, at 12, Rugby Mansions, Kensington, W.14, of bronchial pneumonia, KATE BELINDA FINN, only daughter of the late Eugene Finn, M.D., of Patrick's Hill, Cork. Funeral strictly private. No mourning, no flowers.
Neither mentions her age or date of birth. But Ancestry reveals a birth registration as Catherine Belinda Finn on 16 December 1864, Cork, county of Cork, Ireland, parents Eugene Finn and Belinda (née) McCarthy, who were married on 30 Jan 1864 in Cork. Eugene was the eldest son of James Finn, esq, Kanturk [town in the NW of county Cork], and Belinda was the youngest daughter of Dr McCarthy, Newcastle, County Limerick.
In 1901 Kate Belinda Finn was living (on her own means) at a salubrious address in Kensington with her widowed mother Belinda. Her age was given as 34, which is out by two years (should be 36). Her mother died in 1906 and I can't find Kate in the 1911 census, nor as yet in the censuses prior to 1901. In the 1920s she lived at 12 Rugby Mansions, where her flat-mate was Eileen Florence Hodson Moriarty (1921 and 1931 electoral records). Eileen (b 1880, Ireland, d 1945, Wales) carried on living there for some time after Kate's death and eventually left £35,000 in her own will.
Here is Kate's probate record:
Index of Wills and Administrations, 1932 wrote:FINN Kate Belinda of 12 Rugby Mansions Addison Bridge Kensington Middlesex spinster died 8 March 1932 Probate London 10 May to John Charles Fitzmaurice Finn esquire. Effects £6000 12s. 3d.
£6k is quite a tidy sum for those days. I think that John Finn was her (younger) brother. He spent a lot of time abroad and I suppose it is possible Kate did also, either with him or somewhere warm, for the sake of her health, which might explain where she was in 1911.
As regards her 'chess name', I think I shall carry on using 'Kate Belinda Finn' as that is clearly what she used herself as an adult. The main point of this post was to establish that her date of birth was 16 December 1864 (and not 1870).
EDIT: Rather wonderfully, I've just discovered that Kate's last home, Rugby Mansions, is in Bishop Kings Road in W14. And, equally wonderfully, this is but a stone's throw from where the London Chess Classic is played.