Context: From 1958, the Union Castle shipping line gradually reduced its service calls to the island. Curnow Shipping, based in Avonmouth, replaced the Union-Castle Line mailship service in 1977, using the RMS (Royal Mail Ship) St Helena.

Question: What year did the Union Castle shipping line slowly start to reduce their service calls to the island?
Answer: 1958

Question: Which shipping company replaced Union-Castle Line mailship service?
Answer: Curnow Shipping

Question: What year was Union-Castle Line mailship replaced?
Answer: 1977