[ANNOUNCEMENT] Updated: tzdata 2022f

Cygwin tzcode/tzdata Maintainer Brian.Inglis@SystematicSW.ab.ca
Sun Oct 30 02:34:18 GMT 2022

The following packages have been upgraded in the Cygwin distribution:

* tzdata	2022f

The Time Zone Database (often called tz, tzdb, or zoneinfo) contains
data that represents the history of local time for many locations around
the world, and supports conversion of UTC time to local time at those
locations to allow display of those local times. It is updated
periodically to reflect changes made by political bodies to summer
daylight saving time rules, UTC offsets, and time zone boundaries.
The tzcode package provides the tzselect, zdump, and zic utilities.

For more information, see the project home page:


For more details on changes, see the announcement or below:


	Mexico is dropping DST *TONIGHT* with minimal notice, so this
	upgrade should be applied immediately if affected zones are
	important to your applications, or your clients.
	Other projects are unlikely to be able to update as quickly,
	so prepare to take mitigating actions on other platforms,
	or apply your own patches or updates.
	Some municipalities near the borders may or may not observe or
	drop DST depending on various factors, so more changes may be
	applied retroactively or with no notice in the coming days.

Release 2022f	2022-10-28


* Mexico will no longer observe DST except near the US border.
  Chihuahua moves to year-round -06 on 2022-10-30.
* Fiji no longer observes DST.
* Simplify four Ontario zones.
* Move links to 'backward'.
* In vanguard form, GMT is now a Zone and Etc/GMT a link.

Changes to future timestamps.

* Mexico will no longer observe DST after 2022, except for areas near
  the US border that continue to observe US DST rules.
  On 2022-10-30 at 02:00 the Mexican state of Chihuahua moves from -07
  (-06 with DST) to year-round -06, thus not changing its clocks that
  day. The new law states that Chihuahua near the US border no longer
  observes US DST.

* Fiji will not observe DST in 2022/3.
  For now, assume DST is suspended indefinitely.

Changes to data

* Move links to 'backward' to ease and simplify link maintenance.
  This affects generated data only if you use 'make BACKWARD='.

* GMT is now a Zone and Etc/GMT a link instead of vice versa, as GMT is
  needed for leap second support whereas Etc/GMT is not. However, this
  change exposes a bug in TZUpdater 2.3.2 so it is present only in
  vanguard form for now.

* Vanguard form now uses links to links, as zic now supports this.

Changes to past timestamps

* Simplify four Ontario zones, as most of the post-1970 differences
  seem to have been imaginary. Move America/Nipigon,
  America/Rainy_River, and America/Thunder_Bay to 'backzone';
  backward-compatibility links still work, albeit
  with some different timestamps before November 2005.

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