I think that's going to be hard to guage. Each issue might impact a different VIN range, depending upon the nature of issue.
Some will be problems impacting a whole batch of parts; some, like the transfer case issue, may almost be random, and some issues relating to installation errors, like the brake hoses, will be more related to the actual time on the production line.
So far I think we have UK & continental European vehicles, both petrol and diesel, following the same system. Have we seen or heard of an Australian VIN?