In this guide
The regional time referenceA simple illustrative conversionMidnight changes the date tooDo not use clock arithmetic to invent a local scheduleA complete programme-time noteKeep the service and episode visibleA New Zealand programme time can need a minute-level conversion for the Chatham Islands. Rounding the difference to an hour changes the scheduled instant and can cause a viewer to arrive early or late.
The New Zealand Government and Chatham Islands authorities identify the islands’ distinct time relationship. That clock reference should be kept separate from the broadcaster’s decision about which programme or regional edition to transmit.
The regional time reference
New Zealand’s government guidance identifies a distinct Chatham time relationship, while the local council describes the islands as 45 minutes ahead of New Zealand time. A mainland programme reference therefore should not be copied with the same clock digits by default.
For any specific date, use current official time guidance or an updated location-aware conversion. A clock rule and a programme schedule are different sources: one establishes the time relationship, the other establishes the transmission.
A simple illustrative conversion
This example uses an invented simultaneous programme, not an actual broadcaster listing. If the mainland reference is 20:00 and the Chatham clock is 45 minutes ahead for that date, the same instant is 20:45 in the Chathams.
The minute field matters. Replacing the difference with an hour would yield 21:00, which is a different instant. Leaving the digits at 20:00 would also be wrong for the same simultaneous transmission under that stated relationship.
Midnight changes the date too
For another invented simultaneous transmission, a mainland reference of 23:30 becomes 00:15 on the following local calendar day in the Chathams. A search confined to the original date could therefore miss the relevant listing.
Write the resulting local date beside the time when sharing it with another viewer. A message saying only “00:15” loses whether the programme belongs to the beginning of one day or the night following the previous one.
Do not use clock arithmetic to invent a local schedule
The calculation applies to the same instant. It does not establish that a broadcaster carries the same programme on every regional service or that a locally scheduled repeat follows the same transmission arrangement.
If a programme guide explicitly publishes a Chatham-local listing, use that listing’s own reference. Do not add the difference again. The first task is to establish whether the published digits already represent the viewing location.
A complete programme-time note
| Detail | Illustrative note |
|---|---|
| Programme identity | Fictional simultaneous documentary |
| Original time reference | 23:30 mainland reference |
| Viewing location | Chatham Islands |
| Converted local time | 00:15 on the following date |
| Status | Illustration only; verify actual broadcaster schedule |
Keep the service and episode visible
For a bulletin, identify its exact edition; for a series, retain its episode. The local time calculation cannot establish channel carriage, programme rights or whether a particular external guide exposes a suitable regional listing. It simply preserves the instant once the transmission has been identified.