Looking at the hairstyles, at the strip and the attire of the non players, I'd say it was 1920's wish, which would possibly be Bedlington United.
Millne Park didn't become a football field/ground until Bedlington Mechanics were formed in 1949. The Pavilion / Changing Rooms were behind the goal (nearest the Dr. Pit) and there was banked standing areas along each side-line, but never any covered structure.
My understanding, and confirmed by John Reed (Reedy's Dad) was that there was a very amicable agreement regards rent of the field, between Jimmy Millne and my Grandad. However, once my Grandad had died then there was a deterioration in the relationship between Jimmy Millne and the Football Club's new Committee, not long after they were forced to relocate to the Station Park (the A Pit Recreation Ground).