Kay Griggs-Wright - Colin's second wife - has provided this information (on Facebook).

"I wanted to let you know that Colin Thatcher (ex-World Service News Editor) passed away on December 7th, 2024.
Colin's first wife - Shirley - died in 2012.  I am his second wife, Kay Griggs-Wright, and we were in Knoxville, Tennessee at the time, with my family.  

Though we had been coping with Colin's diagnosis of Alzheimer's Disease from 2021, he had a haemorrhagic stroke on November 17th.
That - and the two ischemic strokes that followed (as a result of having to go off his blood thinners) - kicked his Alzheimer's into high gear.

We able to bring him home, so he died peacefully, being held by his American family.
He is survived by one sister, and both his sons.

He was still active in his Barbershop Group "The Thames Valley Chorus" and took part in their 50th Anniversary Concert on September 28th."