Hi, coreutils 8.29-1 on Arch Linux.
$ date -uIs -d @-62135596801
0000-12-31T23:59:59+00:00
$ date -uIs -d @0000-12-31T23:59:59+00:00
date: invalid date ‘@0000-12-31T23:59:59+00:00’
$
If date thinks it's valid ISO 8601 when it outputs it,
I'd expect it to be considered valid input to take back.
Cheers, Ralph.
