Change Details

They may contain negative UTC offsets, which is allowed by RFC3339, but not by ISO8601. See the last paragraph of https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC for details

They may contain negative UTC offsets, which is allowed by RFC3339, but not by ISO8601. See the last paragraph of https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC for details I also removed `(in UTC)` because it's not true.

They may contain negative UTC offsets, which is allowed by RFC3339, but not by ISO8601. See the last paragraph of https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC for details I also removed `(in UTC)` because it's not true.