On 2024-01-31 18:25, Paul Eggert wrote about 4 transition per year in the foreseeable future:
There's no such feature in tzcode. I don't recall such a feature being discussed - could you point us at any thread in the archive?
From NEWS for release 2014b: Changes affecting code 'zic' and 'localtime' no longer reject locations needing four transitions per year for the foreseeable future. (Thanks to Andrew Main (Zefram).) Changes affecting near-future time stamps New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and Bengt-Inge Larsson.) This is currently an approximation; a better version will require the zic and localtime fixes mentioned below, and the plan is to wait for a while until at least the zic fixes propagate. From Antarctica/Troll in 2023d; # The CET-switching Troll rules require zic from tz 2014b or later, so as # suggested by Bengt-Inge Larsson comment them out for now, and approximate # with only UTC and CEST. Uncomment them when 2014b is more prevalent. Michael Deckers.