As I read it, the value is specifically aligned with "the number of milliseconds since midnight 1 Jan 1970 UTC, leap seconds excluded". (And they really must no

As I read it, the value is specifically aligned with "the number of milliseconds since midnight 1 Jan 1970 UTC, leap seconds excluded". (And they really must not have been considering the rubber seconds in UTC up to 1972!) Consider a day ending in a positive leap second. Suppose that at 23:59:59.500...Z, the millisecond counter is at T − 500. By the start of the leap second (23:59:59.999...Z), the millisecond counter is at T. Then, at the end of the leap second (00:00:00.000...Z), the counter must be at T, since the leap second must excluded from the counter by definition. By 00:00:00.500...Z, it's at T + 500, and so on. The question is, what is the value of the counter between 23:59:59.999...Z (when it is at T) and 00:00:00.000...Z (when it is at T), during the course of the leap second? The definition doesn't make this clear.