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Inconclusive from the photos, either WW or chiffchaff. Hard to judge from the pictures provided.
The second photograph clearly shows the large primary projection of the willow.
For those who may not know primary projection is a measure of how much longer the long primary feathers are when compared to the inner wing feathers, the tertials. The Willow Warbler has longer wings than the Chiffchaff and this shows up as a larger primary projection.
Lat/Lng: 56.8, -5.5
OS grid ref: NM9080