Flock of birds that look like Linnets to me
No interactions present.
You can see the chestnutty back quite well on a few of them. I'm pretty sure you are right.
If you look closely, the flock is entirely Linnets, with not a single bird of another species. Grey heads, brown backs...etc. Often, you might find a mixed finch flock on farmland, but not here.
My Flickr photos...
Lat/Lng: 51.871721768624, -1.0297966003418
OS grid ref: SP668196
Nature reserve on farmland, liable to flooding, so numerous pools that attract waders