im guessing they want to make it more accurate? but why not just shift the current lines rather than create a half time zone? wouldnt this be more confusing?
These three divisions are known as Australian Western Standard Time (AWST), Australian Central Standard Time (ACST) and Australian Eastern Standard Time (AEST). The southern states within these time zones generally adopt daylight savings time during the summer months, whereas the northern states do not. Western Australia, which traditionally does not use daylight savings time, has opted to do so for a trial period of three years from 2006 to bring it's time closer to the eastern states during the summer.
| State | Time Zone | Daylight Savings |
|---|---|---|
| Western Australia | AWST - UTC+8 | AWDT - UTC+9 |
| South Australia | ACST - UTC+9.5 | ACDT - UTC+10.5 |
| Northern Territory | ACST - UTC+9.5 | no daylight savings time |
| Tasmania | AEST - UTC+10 | AEDT - UTC+11 |
| Victoria | AEST - UTC+10 | AEDT - UTC+11 |
| New South Wales | AEST - UTC+10 | AEDT - UTC+11 |
| Australian Capital Territory | AEST - UTC+10 | AEDT - UTC+11 |
| Queensland | AEST - UTC+10 | no daylight savings time |
There are several areas in Australia which do not follow the time zones outlined above:
Broken Hill , a town in western New South Wales uses the ACST time zone of neighbouring South Australia rather than that of it's state.
Eucla , Cocklebiddy , Madura and Mundrabilla on the Eyre Highway in the south-east corner of Western Australia (near the South Australia Border) follow their own unofficial time zone, half-way between Western Australian and South Australian time. Known as "Central Western Standard Time" (CWST) this is 8 hours and 45 minutes ahead of UTC. As Western Australia is now observing daylight savings time this area does also, setting it's clocks to 9 hours and 45 minutes ahead of UTC in the summer months.
Australia's external islands and antarctic territories also follow their own time zones based on their locations.

Imagine the hassle for shipboard IT personnel? I read this recently
"The servers on board most ships are set to Zulu time or Greenwich Mean Time (GMT). That is the one global time zone with a zero offset, the time zone from which all others are calculated. Our US Pacific Time Zone, for example, is currently GMT -8:00. So onboard time-keepers (and computer servers) keep their time constant, which helps ships cruising in different time zones stay synchronized with one another and saves shipboard administrators a lot of hassle. However, the crews and passengers want to know the local time. GMT, or Zulu time, doesn't cut it when it's time to ring the dinner bell out in the South Pacific."
I have seen stories about variable speed master clocks on older ships, where you could set the time/day/distance equation and the clock would run slowly enough during the journey (let's say 5 days from London to New York) and would be on time when they arrived, with no "jumping" for each time zone. All the "slave" clocks throughout the ship would be controlled from the one master time-keeper. On the reverse journey the process and settings would be reversed. Of course you have to make sure the passengers use shipboard clocks and not their own watches, or the captain's table could be a mess!
"Before 1920, all ships kept local time on the high seas by setting their clocks at the morning sighting so that, given the ship's speed and direction, it would be 12 o'clock when the sun crossed the ship's meridian. The local apparent noon is 12 noon."
Like with so many other things, we in the US of A have been insulated from some of the more disruptive effects of wars, like having your time zone changed by invaders (even in the last century). The Japanese changed zones of some of the territories conquered in WW II, but I can't find the articles right now.