Is it AM or PM?
Personally, ive always referenced when the last time i slept more than just a nap. "Late" = i should go to bed, and "Early" = i should BACK to bed.
But that's just me
I believe 'late' can only be stretched so far before there is some noticeable change in conditions. But I don't necessarily think 'early' is the next thing to come along. Rather, 'early' might best be mentioned in reference to earlier only once its later. Also, the latter part of later may itself include indications of the earliest early. Time yields it meaning by being suspended. So...
...'Early' and 'late' happen always at the same time. Only one, however, for us, with our language limitations, radiates at a time.
OK, I'm being silly! ^v^