On 2019-12-06, Arthur David Olson proposed a method to expose in TZif the expiration date of the leap second information:
One odd possibility below.
@dashdashado
Zone Etc/Leapendstat 0 - PRE 2020 Jun 28 0 - POST
Why not produce a tzdb Zone for TAI? As if we had Zone Etc/TAI 0:00:10 - TAI 1972 Jul 1 0:00:11 - TAI 1973 Jan 1 .... 0:00:35 - TAI 2015 Jul 1 0:00:36 - TAI 2017 Jan 1 0:00:37 - TAI 2020 Jun 28 0:00:37 - N_A After all, the Bulletins C of the IERS specify TAI as a function of UTC, just like a tzdb "timezone". Michael Deckers.