Or perhaps it was a "jolly" off the normal route to visit Durban - after 65-years the memory does get hazy as to why they wound up on a beach north of Durban!
As I commented in another thread about the Ysterplaat - Rhodesia routing:
...From my notes recorded whilst at 5 FTS, Harvards for the Rhodesian Air Training Group were shipped from the UK to Cape Town in South Africa and assembled at the RAF Erection Unit located at the South African Air Force base at Ysterplaat near Cape Town.
After assembly they were flight tested and then flown up to Rhodesia by instructors sent down from R.A.F. Thornhill to collect them. Standard procedure was for the pilots to travel down in an R.A.F. Thornhill based 3 Aerial Navigation School (3 ANS) Anson to Ysterplaat. Collect the newly assembled Harvards and fly them up to S. Rhodesia accompanied by the Anson for navigational purposes. From my notes the Harvards and Anson flew via Beaufortwest, Bloemspruit, Pretoria (Zwartkop) and R.A.F. Heany (4 FTS) and then on to 5 FTS...