Don´t you think that the gulls labeled Caspian Gulls in fact are heuglini - considering the darkish upperparts, bill shape and structure. Since heuglini moults later than the more southern Caspian, the standing 1cy 'Caspian' with it´s structure and rather fresh 1st generation coverts and pattern of second generation scapulars with large dark mark at the base and a rather obvious anchor markings, bill shape and large eye looks better for heuglini. The flying 1cy 'Caspian' could of course be a Caspian since the axillaries and underwing looks unmarked and the billshape might also suggest a Caspian. However heuglini might match this also and are quite similar in jizz to many Caspian. The one with the raised wings is in primary moult and together with the pattern and darkness on the primary bases and secondaries fits much better heuglini, at this time of year, the late moulter that it is..