John attended Bristol University and became a Cambridge PhD student of J.W.S. Cassels, but didn't complete his degree. He subsequently worked for Marconi, and later emigrated to Australia and worked at the Australian Bureau of Statistics, before joining the staff at the Canberra College of Education, where he mainly taught computer science.
His MSc "Frattini subgroups" with Mike Newman was awarded in 1967.
I first met John when he was visiting his PhD supervisor Barry Jones in 1973. At this time, John was temporarily on the staff at the University of Central Queensland.
His PhD "Torsion theories for modules over a triangular matrix ring" was awarded in 1978.
I had recently returned from my first study leave, at the University of Nottingham, where I had worked on an extension of Artin's conjecture that had been suggested to me by Christopher Hooley. There was one lemma that I couldn't prove, and to my great relief, John proved it overnight. (See Lemma 12.3, p. 142 of A generalization of Artin's conjecture for primitive roots, Acta Arith. 29 (1976) 113-146.)
After retiring from the University of Canberra, John was a visitor to the ANU mathematics department, and gave two courses in number theory, one being an introduction, the other on elliptic curves.
We kept in touch over the years, especially when I was visiting Canberra during the years 2001-2006.
On one occasion, John told me about his lcm factor refinement algorithm, which I wrote up and coded as a BCMath program.
John published two papers.