On the negative side the bill looked thinner and weaker than 'classic' and the head-shape wasn't too good and if it was a mich it was a small-ish one. In comparison to all other 1st-winter 'Herring Gulls' present (probably c.120) this was a much cleaner, whiter individual that stood out. More homework this morning though, provided a better visual match both in terms of structure and plumage amongst Hans Larsson's 1st-winter argentatus from Sweden. albeit they were taken a month further on in the calendar year.
Apart from an adult Lesser Black-backed Gull the only other interest was another argentatus this time doing it's best 3rd-winter pseudo-smiths impression. (see final image)