Never really looked at one of these close up before, the eyes mounted high and far back looks rather odd.
No interactions present.
So what were the features that suggest it could be this species?
Thanks for the ID suggestions. Looking at the Field Studies Council sheet on Harvestmen I think I can see enough of the relevant features to be happy with P agrestis.
The orange saddle narrows towards the rear and there are paired dark spots. The trident (sort of spike near the eyes) is inconspicuous, indeed I can hardly see it). The occularium (bit with the eyes) is pale (although not to my eye the "silvery-white" that the sheet suggests is the case).
Lat/Lng: 51.540316447216, -0.32921433448792
OS grid ref: TQ159837