The New Zealand Timezone "Daylight Savings Time Delta" field needs to be set to "3600" (no units). This is one hour in seconds.
The start and end times need to be adjusted to match the New Zealand Daylight Savings Time period.
This is confirmed as working as expected in ITSM 17.1.
SDM 12.9 reached End of Service at March 31, 2018, and so any incorrect behaviour with this version can only be corrected manually through the interface at this time, where possible.
No patches will be provided to update the data values or Timezone behaviour.NOTE - What to do if an out-of-the-box Timezone contains incorrect information
Due to the large number of Timezones around the world, and the occasional changes that occur to their definitions, it may be necessary to update the default Timezones that are provided out-of-the-box with CA Service Desk Manager (ITSM).
If you believe that a standard Timezone definition is wrong, please log a CA Support
issue advising what it should be set to.
It would be very helpful to attach a link to an official source
to confirm this data when creating this issue, such as a local government website.
This is because if CA issues a global change to the data, it will impact all sites in the future.
Otherwise, if the change is not official, but seems to be required, please create a post to CA Communities - CA Service Management
to record this for your country, as an aid to other sites. Thank you.