If I recall correctly from the last time I had to deal with this, it's the first 3 towns on the Eyre highway in WA coming from the SA border. This[1] suggests t

If I recall correctly from the last time I had to deal with this, it's the first 3 towns on the Eyre highway in WA coming from the SA border. This[1] suggests there are actually 4. [1]: http://www.postcodes-australia.com/timezones http://www.postcodes-australia.com/timezones