On https://musicbrainz.org/work/08dd1405-f57e-4f0f-86af-e8f767b041aa the relations to the subworks have the "( - ????)" text usually set by the 'ended' checkbox, but the work-work relations are not supposed to have dates
Confirmed by checking the json output (https://musicbrainz.org/ws/js/entity/08dd1405-f57e-4f0f-86af-e8f767b041aa?inc=rels)

Seems to be faulty data directly in the DB, on my local mirror:
musicbrainz_db=# SELECT ended
musicbrainz_db-# FROM link AS l
musicbrainz_db-# JOIN l_work_work AS lww ON l.id = lww.link
musicbrainz_db-# JOIN work AS w ON w.id=lww.entity0
musicbrainz_db-# WHERE gid='08dd1405-f57e-4f0f-86af-e8f767b041aa';
ended
-------
t
t
t
(3 rows)

I guess the easiest is to fix the DB directly since nothing in the interface can set this flag?