Perhaps not just an Oystercatcher?

Last week, when the weather was awful and there wasn't much about there was plenty of talk about this being not just an Oystercatcher and perhaps belonging to the central Asian subspecies longipes. When we first found it today (3rd October), it was alone and the plumage differences were immediately obvious. Later, some other 'normal' Oystercatchers joined it and made the features of brown mantle, longer legs, longer bill and similar appearance even more obvious.