Thought at first this might be a snipe fly, but now not so sure, is a genus even possible?
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I have vague memory from last year of there being two similar species?
Yes, that is why I went for the 'It's likely...'. The similar species is the uncommon R. strigosus. The differentiation comes in the shape of the 3rd antennal segment...pointed in scolopaceus and blunt in strigosus.
As strigosus is found around Box Hill in Surrey, and not much beyond that, yours is likely to be scolopaceus!
My Flickr photos...
Lat/Lng: 53.402986, -2.874159
OS grid ref: SJ419899