The failure is anything particular to the OC43, as OC40 have same system and same mounting. The only explanation my friend got still points to an isolated case. So far, Beneteau did not provide any official communication about the rudder failure on hull #66, but issued a Service Bulletin to increase the resilience at upper rudder post bearings. I don't know if such bulletin apply to every OC series, or from a specific number, neither if this is a specific to these boats. Anyway, my hull #66 is preventatively under service, despite not showing any sign of failure.
So far, nobody reported any analisys on what happened. We don't know if the system was damaged by the autopilot engaged under heavy load, nor if the boat hit anything submerged, or this is a design/mounting failure.
Check here the failed rudder. The upper post became loose, so skipper attached a line, disconnected the autopilot, in order to not further damage the rudder system.
Note the loose upper bearing. The mirror shows behind, in a difficult spot.
After repair started, you can see the upper collar removed. Note how it was pulled out of original bond to the hull.
Now, new bearing is re-inserted, but its void around it, will be completely filed with epoxy to increase the bond to the hull.
Note the epoxy mask on the wood. At least, looks far more robust.
Final touch. Another plastic ring screwed to the wood, brings even more hardening to the original system.