[tz] OpenJDK/CLDR/ICU/Joda issues with Ireland change

[Guy Harris]

On Jan 25, 2018, at 7:57 AM, Clive D.W. Feather <clive at davros.org> wrote:

> What about the name for the third offset each year? The UK used to use
> three offsets during the year. I'm sure it was not alone. I'm certainly not
> sure that it won't happen again.

So if we have three flavors of time per year, with different names/abbreviations/offsets, that would require a POSIX API change, and changes to other time-related APIs that have an assumption that, within a year, there is, at most, winter time and summer time.