Hebrew Character (Orthosia gothica)
It is not hard to see why it bears that name; that distinctive mark on the wings.
The Hebrew Character is a resident species as opposed to migratory. It overwinters as a pupa and hatches into an adult and is flying in March and April and is particularly fond of Sallow blossom.
It is single brooded and the larvae hatch and are active on a wide variety of trees during May and June before pupating.