A Wickford Teacher of the early 20th century?

I have been researching my family for some years now. It’s been a long haul, as I have lived in Australia since 1989 and am doing it all by long distance.  My parents died over 40 years ago so I have been unable to use them for any assistance.   I do know that some time during the early 1920s my father, his brother and parents lived in Stock, Essex.  Their surname was Sibley.

I have now come across a Great Aunt of my father, her name was Edith Dagmar Plantagenet Hayes.  She was a School Mistress in Wickford during the 1920s, and possibly earlier.  She died in 1929 and lived at “Belvedere”, London Road, Wickford, Essex.

(She appeared to have a sister called Dorothy M Hayes who married an Alfred J T Madle in 1918 in Chelmsford.)

Would there be any records of Edith Hayes as a school teacher and if so where she taught?    If anyone can shed any further light on her it would be extremely helpful.