Anyone with a good spotting location, or inside knowledge might be able to assist with confirming this. It apparently had it's engine replaced this past week, and is getting some electronics upgrading to be compatible with the other trains in the One Rail fleet.
For the benefit of those that don't know, V544 was bought by Freight Australia (which later became or was merged into pacific national) as an insurance replacement for G517 and G518 following a significant accident at Ararat in 1999. It is a GT46C and is approximately the same as the Q and FQ class, and has been an orphan in the PN fleet. It was used on the coal train that once ran to Leigh Creek, and has been idle for a number of years following an engine failure shortly before the Leigh Creek service terminated.