Garden Flies

Hi all. I have been photographing flies in my North Devon Garden for two years now and there are a  lot more than I thought there were ! Even the ones I thought were straight forward eg Bluebottles and Greenbottles are more varied that I thought. So I am a beginner but I am slowly starting to learn more about them but do rely on trying to ID from photos which does make it extra hard but still interesting. I I record any I can ID and have a lot of help from the Hoverflies and Diptera facebook pages with this . Today is pretty cold but still a few flies in the garden trying to soak up some sun. Fannia and Calliphora I think but would welcome any tips/thoughts on this , many thanks