On 2021-01-24 18:53, Paul Eggert wrote:
I replied to that survey, basically saying that currently our work is based on two timescales (TAI and UTC) and that I hope they don't turn it into four (TAIold, UTCold, TAInew, UTCnew).
Or would it be three? That would be even more confusing....
No new time scale and no new time scale designations would be created. The change would just be a redefinition of UTC, to be applied beginning with a date in the future (and probably a redefinition or abolition of DUT1 and possibly of dUT1). The last such redefinition of UTC applies since 1972. No new time scale and no new time scale designations were created then, nor would any be created with a future redefinition -- much the same as for the redefinition of the SI units kg, A, K and mol in 2018, where the old names and symbols have been retained. As far as tzdb is concerned, the leap second table would just end for good (perhaps with TAI = UTC + 42 s), and the "right" tzdb timezones would become unnecessary for time stamps from then on. As would the zoo of "leap second smearing" schemes in computer system time demons. Michael Deckers.