[tz] Unacceptable recent changes

[Petr Machata]

Stephen Colebourne <scolebourne at joda.org> writes:

> The point I'm making is that end-users of this data assume it to be
> stable and reliable. Moreover, the vast majority of those users do not
> care whether the data pre-1970 is accurate or not. Stable yes,
> accurate no.

I don't think you can assume stability either.  We occasionally revisit
old data to correct them.  There's some guesswork involved in the way
some zones are defined even in relatively recent past, let alone
pre-1970, and when better information becomes available, those entries
are changed.

Thanks,
PM