It was larger and plumper than a Black Headed but smaller than the juv Herring gull below it, with a near full black hood and a longer dark bill with slight black streaks on the ends of the primaries.
Only just gone through the pics but to me it looks good for a 2nd winter Med gull. Unfortunately this morning it appeared from nowhere , scope was packed up and one of those cases of try ID it or get a pic.
BS