This individual has rather odd, pale greater coverts
This is a rather strange, pale bird. It has a gentle facial expression and a jizz not unlike Iceland Gull. I always struggle to decide whether birds such as this are simply extreme, pale Herring Gulls or sufficiently pale and odd they they are likely to be hybrids.
Very unusual to see covert moult in first winter Herring Gulls. This bird seems to be dropping many feathers simultaneously, without replacement; perhaps this suggests some problem rather than being moult sensu stricto.