Proposed change to time zone northamerica file: deferred Cuban DST

Steffen Thorsen straen at
Wed Mar 12 12:45:55 UTC 2008

It seems that Cuba will start DST on Sunday, 2007-03-16, two weeks earlier than expected (or one week later than current tzdata).

It was announced yesterday, according to this source (in Spanish):

Some more background information is posted here:

The article also says that Cuba has been observing DST since 1963, while Shanks (and tzdata) has 1965 as the first date (except in the 1940's). Many other web pages in Cuba also claim that it has been observed since 1963, but with the exception of 1970 - an exception which is not present in tzdata/Shanks. So there is a chance we need to change some historic records as well.

One example:
> Al finalizar el conflicto bélico se eliminó de nuevo esa 
> costumbre y fue retomada en 1963. Desde entonces, empezó a aplicarse 
> regularmente todos los años, salvo en 1970.

Best regards,
Steffen Thorsen -

Arthur David Olson wrote:
> Since this affects current time stamps, it's probably best to get a best
> guess out the door rather than wait for documentation. Here's a proposed
> change to the time zone package "northamerica" file to reflect the deferred
> start of DST in Cuba.

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