Você pode obtê-lo do github na verdade, ele foi modificado há 5 dias.
veja link para o arquivo southamerica
tz
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Southern Brazil starts DST two weeks later in 2018
* NEWS: Mention this.
* southamerica (Brazil): New rule just for spring 2018.
eggert committed 5 days ago
- Rule Brazil 2018 max - Nov Sun>=1 0:00 1:00 -
+ # From Fábio Gomes (2018-10-04):
+ # The Brazilian president just announced a new change on this year DST.
+ # It was scheduled to start on November 4th and it was changed to November 18th.
+ # From Paul Eggert (2018-10-04):
+ # This attempts to avoid confusion during the November 4 and 11 national high
+ # school exams, which were mis-scheduled. Guess that it's just this year.
+ Rule Brazil 2018 only - Nov Sun>=15 0:00 1:00 -
+ Rule Brazil 2019 max - Nov Sun>=1 0:00 1:00 -
Quanto a publicar a nova atualização nas tabelas oficiais da TZ - também conhecida como 2018f :
[tz] Another change on Brazilian DST time
Paul Eggert eggert at cs.ucla.edu
Thu Oct 4 15:37:17 UTC 2018
I just now updated the development version
https://github.com/eggert/tz with the attached patch, and you can
use that now if you like. I'd like to plan for a new tzdb release
soon after the presidential decree is published (please let me know
when that happens).