There was a large beacon on Cust Rock (part of a very awkward cluster including Rumsey Rocks between TST and Hung Hom). The danger was marked with a buoy in 1909, but in 1929 a fixed beacon was erected on top, not far in front of the Signal Hill (Blackhead Pt) light that had been lit in 1909. Once the Cust Rock Beacon had been lit, someone worked out that money could be saved by having only one light, not two, so in 1933 TST light was extinguished and the Cust Rock Beacon upgraded (Fl. 4s 25' 10M - i.e. one flash every 4 seconds, light 25' above the sea, visible 10 nautical miles away in good visibility from a height of eye of 15').
Post-war the light was reinstated - it is shown working on a copy of the Emergency Chart 9215 sent by Mardep to the UK Hydrographic Office in early 1952 and we know from newspaper reports that all pre-war lights had been relit by 1948, most having been reinstated by end 1947.
Comments
Decommissioning of Cust Rock Beacon
Cust Rock was absorbed into the Hung Hom mainland after reclamations in 1962 and the light apparatus was removed in 1963. The structure would have been demolished soon after.
Rumsey Rock
Cust and Rumsey Rocks were quite far out in the Hung Hom Bay before reclamation. See this 1915 map: