build(deps): bump tzdata from 2025.3 to 2026.3

[dependabot]

Bumps tzdata from 2025.3 to 2026.3.

Release notes

Sourced from tzdata's releases.

2026.3: Release of upstream tzdata 2026c

Version 2026.3

Upstream version 2026c released 2026-07-08T17:23:58+00:00

Briefly:

Alberta moved to permanent -06 on 2026-06-18. Morocco moves to permanent +00 on 2026-09-20. More integer overflow bugs have been fixed in zic.

Changes to future timestamps

Alberta’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -06 thereafter. (Thanks to Roozbeh Pournader and others.) Model this with its traditional abbreviation CST. Although the change to permanent -06 legally took place on 2026-06-18, temporarily model the change to occur on 2026-11-01 at 02:00 instead, for the same reason we introduced a similarly temporary hack for British Columbia in 2026b.

Although another TZDB release will likely be needed soon because Northwest Territories will likely follow Alberta, the legal formalities have not yet taken place.

Morocco plans to move back to permanent UTC, without daylight saving time transitions, on 2026-09-20 at 02:00. This also affects Western Sahara.

Changes to commentary

Northwest Territories is expected to move to permanent -06 prior to 2026-11-01 02:00, when clocks would otherwise fall back. (Thanks to Tim Parenti and James Bellaire.) Model this with its traditional abbreviation CST. Unfortunately the change is not yet official, so it is currently present only as comments that can be uncommented as needed.

2026.2: Release of upstream tzdata 2026b

Version 2026.2

Upstream version 2026b released 2026-04-23T06:06:43+00:00

Briefly:

British Columbia moved to permanent -07 on 2026-03-09. Some more overflow bugs have been fixed in zic.

Changes to future timestamps

British Columbia’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -07 thereafter. (Thanks to Arthur David Olson.) Although the change to permanent -07 legally took place on 2026-03-09, temporarily model the change to occur on 2026-11-01 at 02:00 instead. This

... (truncated)

Changelog

Sourced from tzdata's changelog.

Version 2026.3

Upstream version 2026c released 2026-07-08T17:23:58+00:00

Briefly:

Alberta moved to permanent -06 on 2026-06-18. Morocco moves to permanent +00 on 2026-09-20. More integer overflow bugs have been fixed in zic.

Changes to future timestamps

Alberta’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -06 thereafter. (Thanks to Roozbeh Pournader and others.) Model this with its traditional abbreviation CST. Although the change to permanent -06 legally took place on 2026-06-18, temporarily model the change to occur on 2026-11-01 at 02:00 instead, for the same reason we introduced a similarly temporary hack for British Columbia in 2026b.

Although another TZDB release will likely be needed soon because Northwest Territories will likely follow Alberta, the legal formalities have not yet taken place.

Morocco plans to move back to permanent UTC, without daylight saving time transitions, on 2026-09-20 at 02:00. This also affects Western Sahara.

Changes to commentary

Northwest Territories is expected to move to permanent -06 prior to 2026-11-01 02:00, when clocks would otherwise fall back. (Thanks to Tim Parenti and James Bellaire.) Model this with its traditional abbreviation CST. Unfortunately the change is not yet official, so it is currently present only as comments that can be uncommented as needed.

---

Version 2026.2

Upstream version 2026b released 2026-04-23T06:06:43+00:00

Briefly:

British Columbia moved to permanent -07 on 2026-03-09. Some more overflow bugs have been fixed in zic.

Changes to future timestamps

British Columbia’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -07 thereafter. (Thanks to Arthur David Olson.) Although the change to permanent -07 legally took place on 2026-03-09, temporarily model the change to occur on 2026-11-01 at 02:00 instead. This works around a limitation in CLDR v48.2 (2026-03-17). This temporary hack is planned to be removed after CLDR is fixed.

... (truncated)

Commits

• a442794 Update tzdata to version 2026c (#145)
• 8f35937 Use the release environment for TestPyPI publishes (#146)
• ba0b891 Few fixes to the maintaining doc
• 9a7e6a0 Add Stan Ulbrych to license
• 1cab5e2 Bump actions/checkout from 6.0.2 to 7.0.0 (#144)
• e71cff9 Bump hynek/build-and-inspect-python-package action (#143)
• 14b2953 Make open PR check stricter (#141)
• 68d4d51 Isolate package build and publish (#137)
• 5bb6232 Fix punctuation in README.
• e313d95 Raise with an informative message when release is missing from NEWS file
• Additional commits viewable in compare view