A switch to a more southerly airflow but my early morning circuit produced the same suite of migrants with just 5 Redwing and a Blackcap seen at Skaw and then 2 Redwing, a Black Redstart, the Yellow-browed Warbler, 3 Brambling and a Chaffinch at Leawart and a Chiffchaff at Valyie. I decided to walk the geos at Lamba Ness that produced a single Chiffchaff and a single Eastern Lesser Whitethroat. We then saw the Eastern Lesser Whitethroat at Haroldswick but a check of a couple of sites at Baltasound drew a blank.
Bramblings and Chaffinch at Norwick
Black Redstart at Norwick
Chiffchaff at Lamba Ness
Rock Pipit at Lamba Ness
Whilst littoralis typically undergoes a post-breeding moult in Aug/Sept rendering them unidentifiable from petrosus, with this individual showing several traits (grey crown, pale supercilium & pinkish-tinged throat) of the subspecies, I'd be surprised if it wasn't one.
Al returning from Foula?
