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It's not an Epistrophe, as they have spots on tergite 2 (the first visible abdominal segment behind the thorax) which meet the margin broadly. On this fly, the spot is pinched in at the margin, leaving what looks like a spot the shape of a golf club head.
So it is a Syrphus. To get to species, you need to be able to see presence/absence of hairs on the eye, colour of hind femora, presence of tiny hairs on basal cells of wing and so on...a microscope job, really.
My Flickr photos...
Lat/Lng: 50.8582, 0.5683
OS grid ref: TQ808096