(a) Dockage shall begin against a vessel when:(1) making fast to a wharf, dolphin, or other structure;(2) occupying a berth immediately alongside a wharf;(3) making fast to a vessel alongside a wharf or to another vessel already made fast to a vessel alongside a wharf;(4) the first boat, raft, lighter, etc., reaches a wharf.(b) Dockage shall continue upon such vessel until she is completely freed