[tz] Will Morocco switch from +01 to +00 during Ramadan next year?

Paul Eggert eggert at cs.ucla.edu
Thu Nov 1 18:32:35 UTC 2018

On 11/1/18 10:59 AM, Matt Johnson (AZURE) wrote:
> The cited articles appear to be opinions and surveys only.   I would like to see something, anything, from an official source

I'd also like to see something official. However, the Moroccan 
government appears to have made last week's announcement at the last 
minute to suppress political controversy that could have derailed the 
change, and it's not implausible that they'll do something similar for 
next year's Ramadan change - which would be a real problem for us and 
our downstream data users.

When there's a conflict between "official" and "practical" time for past 
timestamps, I have preferred "practical" time on the grounds that users 
typically prefer the timestamps they actually used. This recently came 
up for El Paso, which would require its own Zone line if tzdata merely 
recorded official US time zone legislation; but tzdata doesn't do that, 
and instead reflects the timestamps that the vast majority of El Pasoans 
actually used during the period in question.

Similarly, for Morocco we now have the situation where the government's 
officially announced plans do not currently include a Ramadan fallback. 
Here, too, we have a conflict between "official" and "practical" time, 
the main difference being that here the timestamps in question are 
predicted timestamps, not past timestamps.

This is a judgment call, and I could certainly see the call going the 
other way in other circumstances. However, in this particular instance 
the case for including the guessed change is reasonably compelling: 
people on the ground are telling us that a Ramadan fallback is most 
likely what will happen, a poll has been published saying there's a 
broad consensus for a fallback, and Morocco has been doing such 
fallbacks for five years already. tzdata is always guessing about the 
future, and it's better to make the best guess we can even when the 
guess isn't official yet. (Besides, if we guess wrong now we can always 
fix it later. :-)

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