Did they actually do anything to tailor it to Aus roads? A quick google doesn't show much...
This was about it
https://www.goauto.com.au/news/hold...tuned-for-aussie-tastes/2017-08-25/65074.html
“They have taken the steering calibration and adapted it to be specific to that vehicle (VXR),” he said at Holden’s Lang Lang Proving Ground. “The suspension, we have given them feedback.”
The Insignia was also sent to the UK, where the B roads are generally terrible, perhaps piggy backed those settings? I'd imagine the rates were tuned a little, but can't see the hardware being changed.