my friend James 9V1YC has sent me a scan of an old QSL card with my today’s call sign 9V1MS.
I did some research about Denis Mather G3KAM/9V1MS.
He lived at Jalan Jintan, near Orchard Road, right around the corner of the Gleneagles hospital.
I found out that he in summer 1970, he had already moved to 43 Hillcrest, Curepipe, Mauritius, having the new callsign VQ8CZ, see here
Other callsigns of Denis Mather were 9V1MS, 9M8MS, and GM3KAM, see here