Some signs of overheating there, this is linked to plenty of problems.
Significant head recession, burnt oil under head and under piston
To get those oil stains after 150 hrs would be pretty hot
Some of the older piston had casting dags/lumps in these areas shown as ground
Jab direct pairing pistons, gives weight limits, and doesnt allow rebore of barrels, so did Camit.
Not sure how Jabiru claimed it was a Camit engine originally and not their fault?