I though of some sort of Pipit. I made a video of it and uploaded it as a House female sparrow but looking at a still it's all wrong . The beak is definitely too thin and wrong colour and the ring round it's eyes, The expression on it's face is not that of a Sparrow. It was rummaging on the Exe estuary
perhaps the change their legs for the winter or when they get older. I'll have a look in my encyclopedia
(Could be in The Wrong Trousers
)
Might be a Juvenile Rock Thrush?