I was down in the Cotswolds at my brothers recently where I found an old copy of 'The Armourer' magazine. Issue 80, March/April 2007. On the letters page was a photo question from one of Gerry's old comrades. I have reproduced it here.
It shows 8 members of the North Irish Horse in 1940/41 wearing 'SP' armbands. The question was, does anyone know what they represented?