He flew in HR623 from Kinmagon on 4th and 6th of June 1945. I believe (ie saw on the www somewhere!) the 618 Squadron aircraft went by sea direct to Australia for planned use in highball ops. Perhaps when this plan was abandoned some of the aircraft were redeployed. But would these be FB VI?
I will probably get the Squadron Records of Events for the months of his ops to find out a little more about what the Squadron was doing while he was with them, this would also confirm the serial in the log.
I have found that his pilot , who I only had a rank and surname for, was F/Lt J.K.Wardrop, an Australian and I'm almost certain RAAF. I was pleased to find that he also survived, in fact he was home and demobbed while Arthur still had a few months of flogging around south east asia in Dakotas ahead of him.
Just looked up 618 on Wiki - they received 12 FB VI in Feb '45 to be used to maintain crew currency without risking the carrier/highball modified aircraft - probably it was one of these?