Offset for America/Chihuahua possibly wrong?

[Hancock, David (DHANCOCK)]

Our company provides flight-support services to business aviation, and
we use the TZ database from our web-based flight-planning pages to allow
date entry in local or Zulu time. One of our Mexico-based customers
called to say our offset was wrong for the airport MMHO (Hermisillo).
We're getting GMT-6 from our Olson database. We called two places at
that airport, and both report that they are GMT-7.

The specific timezone reference is America/Chihuahua, and we are using
the 2008f dataset.

Does anyone have any clues about the America/Chihuahua offset? It's not
due to go off DST until 10/26, but it appears to be off by one hour NOW.

Thanks for any assistance you can provide.

Cheers!
--
David Hancock | dhancock at arinc.com


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