The 1939 register provides a birthday for Frank Ellis etc.
7 Winster Road, Sheffield
Ellis Frank, May 4 1880, labourer – wire mill
Ellis Tom, Feb 19 1920 Unemployed
Ellis (Dunkerly struck out) Lily Oct 11 1882, unpaid dom work
Dunkerly Walter Jan 13 1916, Inserting twist drills and progressing engineers small tools
Next entry struck out (born less than 100 years ago)

With the birthday you might be able to narrow down birth options at GRO & mother’s maiden name.

At GRO there is one Frank Ellis registration 2nd quarter 1880:
ELLIS, FRANK mother's maiden name FISHER
GRO Reference: 1880 J Quarter in SHEFFIELD Volume 09C Page 468

I'm a bit late on the scene. There seems to have been active discussion at https://www.sheffieldforum.co.uk/

Thanks very much for your message, will check out Sheffield Forum!