Lights to display on tug for ATB when at anchor

Has anyone been able to find a definitive answer for what lights the tug should display on an ATB unit when at anchor? I have an opinion but that’s all, just trying to find the correct answer once and for all.

IIRC, when Anchored my Rig Displayed the Anchor (360 Degree White Light) on the Bow Mast on the Barge.