As the name clearly suggests, this moth appears in the autumn and overwinters as an adult. It’s on the wing from September to October, and again briefly in March and April to lay eggs. The larval food-plants are rowan (Sorbus aucuparia) and willow (Salix spp.). These tree species are sporadic over the archipelago, so the moth could appear almost anywhere.

References: 
Leverton, R. & Cubitt, M. (2024). The Larger Moths of Scotland.
Waring, P. & Townsend, M. (2018 third edition). Field Guide to the Moths of Great Britain and Ireland.