Yes, I've seen that. Do you have a link to the spec (see original question)? The 2000 spec was superceded by the 2004 spec which is available for purchase at https://www.iso.org/obp/ui/#iso:std:iso:8601:ed-3:v1:en. But I can not find a published version of it.
Edit: An older working doc: http://www.loc.gov/standards/datetime/iso-tc154-wg5_n0038_iso_wd_8601-1_2016-02-16.pdf. In this doc the only examples of "expanded" format datetimes have separators in both date and time. Another piece of circumstantial evidence ...
In reply to Re^3: Does ISO8601 require a separator in the time if one is used in the date?
by 1nickt
in thread Does ISO8601 require a separator in the time if one is used in the date?
by 1nickt
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