Sept. 24, 2021
12:16 a.m.
On 9/22/21 15:23, Howard Hinnant via tz wrote:
Before the change the tzdb does a “best effort” on pre-1970 dates.
No, quite the reverse. There are many places in 2021a where we have some data (often unreliable) about pre-1970 timestamps, and we put that data into 'backzone' instead of doing a "best effort" on pre-1970 dates in the default database. Examples include Africa/Addis_Ababa, Africa/Freetown, and Asia/Harbin. I expect that there are more Zones in 2021a where this sort of thing happens, than Zones in the changes being discussed. There's a lot of precedent for the recent changes, and a lot of experience for the fact that the fallout from this kind of change is negligible in practice.