Also - and you guys are going to love this - I looked up the coordinates we have for America/Santa_Isabel in zone.tab, which are +3018-11452, and look what I found:
We've picked "Sierra Santa Isabel" - a mountain range. :)
Nowhere near the actual town of Santa Isabel either.
> To: gregsla@microsoft.com; tz@iana.org
> From: eggert@cs.ucla.edu
> Date: Fri, 9 Oct 2015 13:31:56 -0700
> Subject: Re: [tz] America/Santa_Isabel
>
> On 10/09/2015 10:47 AM, Greg Slayden wrote:
> >
> > I see conflicting information online about when DST ends there, either
> > November or October. Making contact with locals in that area is likely
> > the best way to find out
> >
>
> Yes, if we can establish that San Quintín uses Mexico's DST rules, we
> can effectively replace America/Santa_Isabel with America/San_Quintin.
> Normally we'd prefer Lázaro Cárdenas as it has more people, but it's an
> ambiguous name whereas San Quintín is not.
> From: eggert@cs.ucla.edu
> Date: Fri, 9 Oct 2015 13:31:56 -0700
> Subject: Re: [tz] America/Santa_Isabel
>
> On 10/09/2015 10:47 AM, Greg Slayden wrote:
> >
> > I see conflicting information online about when DST ends there, either
> > November or October. Making contact with locals in that area is likely
> > the best way to find out
> >
>
> Yes, if we can establish that San Quintín uses Mexico's DST rules, we
> can effectively replace America/Santa_Isabel with America/San_Quintin.
> Normally we'd prefer Lázaro Cárdenas as it has more people, but it's an
> ambiguous name whereas San Quintín is not.