Most GNU/Linux distributions, Android, iOS, macOS and Microsoft Windows
all have at least version 2025a of TZDB, so properly-updated
installations should be working correctly after Paraguay's rule change
yesterday. However, Repology reports[1] that the latest stable versions
of the following GNU/Linux distributions are still based on TZDB 2024b
and thus presumably are misbehaving in Paraguay:
Apertis, nixpkgs, OpenWrt, Pardus, Rosa, Trisquel, Ubuntu
Of these Ubuntu is best known, and it has several downstream distros
that I assume are also affected. So Ubuntu may be the most important
laggard for Paraguay.
In the list above, I omitted distros like Adélie that use TZDB versions
that predate 2024b. I assume these distros are not intended to be
up-to-date, are no longer maintained, have distro-specific patches, or
aren't tracked accurately by repology.
Many other systems also may be out of date for Paraguay; see the first
paragraph of the section "The tz database"[2] for a partial list. I
haven't tried to track them all.
[1]: https://repology.org/project/tzdata/versions
[2]: https://data.iana.org/time-zones/tz-link.html#tzdb
