The 2017a release of the tz code and data is available. It reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes:
Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
discontinues DST.
Changes to future time stamps
Mongolia no longer observes DST.
Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
Its clocks diverge from America/Santiago starting 2017-05-13 at
23:00, hiving off a new zone America/Punta_Arenas. Although the
Chilean government says this change expires in May 2019, for now
assume it's permanent. This also affects Antarctica/Palmer.
Changes to past time stamps
Fix many entries for historical time stamps for Europe/Madrid
before 1979, to agree with tables compiled by Pere Planesas of the
National Astronomical Observatory of Spain. As a side effect,
this changes some time stamps for Africa/Ceuta before 1929, which
are probably guesswork anyway.
Ecuador observed DST from 1992-11-28 to 1993-02-05.
Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
