Made a buzzing call.
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On probability Willow would be my 'favourite' too. Willows tend to 'chay chay chay' while Marsh Tits tend to sneeze with a 'pitchow' of give a two noted see-saw call.
The 'long' pale cheek patch, without any buff colouration towards the rear of the cheeks, points towards Willow Tit -and I think that I can just about make out a pale wing panel when the image is enlarged (that may be my imagination though!).
In combination with the description of the call Willow seems to be the correct ID.
I agree with all of the above, and would add that the "bull-necked" appearance is also a willow tit feature.
Lat/Lng: 53.5, -2.7
OS grid ref: SD5802