There's more to the story ...
The CX Capt heading to the RFDS is a (relatively) junior Captain who was assigned across to the Airbus from the -400 a few years ago. He's been commuting to PER (with difficulty) while waiting for a basing (which isn't going to happen), hence the move. He's also been given grief with housing in HK, so no surprise he wants out.
His wife has recently qualified as a nurse/midwife and is going to join the RFDS too, so I'm told.
As for him getting used to night flying, he's well practiced at it. That's 90% of what we do on the Airbus. Single Pilot too, given the lack of experience most new joiners are arriving with.
Will miss flying with him. He's a good guy.