Version 2025.1

Upstream version 2025a released 2025-01-15T18:47:24+00:00

Briefly:

Paraguay adopts permanent -03 starting spring 2024. Improve pre-1991 data for
the Philippines. Etc/Unknown is now reserved.

Changes to future timestamps

Paraguay will stop changing its clocks after the spring-forward transition on
2024-10-06, so it is now permanently at -03. (Thanks to Heitor David Pinto and
Even Scharning.) This affects timestamps starting 2025-03-22, as well as the
obsolescent tm_isdst flags starting 2024-10-15.

Changes to past timestamps

Correct timestamps for the Philippines before 1900, and from 1937 through 1990.
(Thanks to P Chan for the heads-up and citations.) This includes adjusting local
mean time before 1899; fixing transitions in September 1899, January 1937, and
June 1954; adding transitions in December 1941, November 1945, March and
September 1977, and May and July 1990; and removing incorrect transitions in
March and September 1978.

Changes to data

Add zone1970.tab lines for the Concordia and Eyre Bird Observatory research
stations. (Thanks to Derick Rethans and Jule Dabars.)

Changes to documentation

The name Etc/Unknown is now reserved: it will not be used by TZDB. This is for
compatibility with CLDR, which uses the string "Etc/Unknown" for an unknown or
invalid timezone. (Thanks to Justin Grant, Mark Davis, and Guy Harris.)

Cite Internet RFC 9636, which obsoletes RFC 8536 for TZif format.