There were 2 of these birds calling to each other in neigbouring apple trees, & feeding.
No interactions present.
Thanks for the comments which confirms my own suspicions, the shots were with alimited range of optical zoom with only a chance of turning out. By the way the call sounded to me like a sweep sweep or syreep.
Willow Warbler's call is rather more disyllabic than Chiffchaff's monosyllabic 'hweet'.
My Flickr photos...
The eye-stripe and supercilium both seem rather strong for a typcal Chiffchaff. I have seen a good number of family parties of Willow Warblers in the last few days and these seem to be calling to one anther noisily as they feed (and travel south?).
Some thin exta support for this species perhaps.
Alan Brampton (Benson)
You've done well to see juveniles! I ringed 16 Willow Warblers, yesterday morning, and only 4 were young birds. Normally, that ratio would be the other way round. I think, like some other small birds, they really struggled to breed, this summer.
I also think Willow is most likely, but some larger adult Chiffchaffs can be very similar.
thanks again for all your worth contributions
Lat/Lng: 52.5, -1.2
OS grid ref: SK5500