Wow!! Is this for real. Australia has adopted one of our rules. Usually the excuse to change our rules is to align with Oz.
It is known here as the "lapped on" rule. It applies to horses who gallop across the finish line in a break when there are other finishers within a length behind.
It only applies to crossing the finish line and provide definitive certainty whether a breaker holds or loses it's placing irrespective of gaining advantage when in a break over the line.
What happens prior to the line is covered by other rules. Ours provides for auto disqualification if a break of more than 50m in final 200m or 150m prior to the final 200.