On 2020-11-16 14:15, John Sauter wrote:
In addition, following Steve Allen's suggestion, the start of the leap second in the time scale after the step could be 2017-01-00T23:59:59.
Yes, it is. But I am not aware of an official definition of what a leap second is. A positive leap second is usually taken to be a (left closed and right open) interval of length 1 s of TAI values that are not associated with UTC values by the function from UTC to TAI as published by the IERS. For the latest leap second this interval was [2017-01-01T00:00:36..2017-01-01T00:00:37[; while TAI was in that interval, UTC could be 36 s or 37 s less than TAI, and ITU recommends the use of their leap second notation for the value of UTC. Michael Deckers.