Sad news.
I did see Henry Willis once. I used to go to the Swansea festival in Wales, UK for a number of years. Originally, they were three weeks long and, if you planned it properly, you could find something to see or listen to almost every day.
I live a long way away but my mother was based at the air base nearby during WW2. That was when Swansea was bombed. A couple of the bombs adversely affected the Guildhall in February 1941. The incendiary bomb that hit the roof did not damage the organ directly but the rain it subsequently let in did. It damaged the original Echo organ. That was later remodelled and ended up with the rest of the pipework as a Positif organ.
I have just looked at their booklet on the organ and it looks as if it was being restored during the 1980's with an estimated completion date of 1984. I went to the organ's first outing after its renovation and Henry Willis was there. He appeared on stage and took a bow for the work his company had undertaken. We never met but he looked to be a somewhat flamboyant and extrovert individual.
A famous name will now be missing from the organ scene.