[tz] Astrakhan region got approval to change its time zone

[Paul Eggert]

Matt Johnson wrote:
> I'm more concerned with end-user confusion on whether +04 means GMT+04 or MSK+04.

No abbreviation will be confusion-free; all we have are imperfect alternatives. 
That being said, it seems unlikely that English-language users would naturally 
interpret "+04" to be relative to Moscow. In practice, I expect the more common 
mistake would be to interpret "+04" as being west of Greenwich instead of being 
east. For that, we'd just have to remind users that we're using the ISO standard 
for the sign.

Surely "+04" would be more likely to be interpreted correctly than "AST" or 
"ASTT" or any other alphabetic abbreviation we might invent. Plus, numeric 
abbreviations generalize nicely to situations outside Russia, where we have 
similar issues.