Sanderling - light grey upper, shorter (no decurve) bill than Dunlin
Turnstone - rich chestnut upper parts
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iSpot does work better on identifications of single species, though, like your last one, of Redshank. If you can put the pics up separately for each species, that works a lot better, really.
My Flickr photos...
Lat/Lng: 51.3827, 1.3276
OS grid ref: TR316701