Blue-Headed / Yellow Wagtail - subspecies?

Blue-Headed / Yellow Wagtail - subspecies?

Observation - Blue-Headed / Yellow Wagtail - subspecies? - UK and Ireland. Description: In amongst all the Yellow Wagtails was this - clearly different (Although the poor photo doesn't help here)

In amongst all the Yellow Wagtails was this - clearly different (Although the poor photo doesn't help here)