Someone kindly emailed to say they had a painting possibly by “Annie Swynnerton” (her name being written on the back of the frame) and asked for an opinion on the attribution.
With a bit of study, it seemed to resemble one of the obscurer images in one of the 1923 exhibition photographs, the one just partly visible at the bottom right of the photo. With a bit of computer trickery imposing the one image on the other, the match became more obvious.
The white blob at the bottom left of the painting in the photo is a blemish on the film, not part of the painting.
The painting is unnamed, so I have christened it “Landscape with figures.”
Jonathan Russell … with sincere thanks to the person who sent the email.