Wikimedia Bugzilla is closed!

With all cookies deleted:
* Log-in on w:en with user name xxBot (is not unified account) - OK

* Log-in on w:nl with user name xx (is unified account), resulting in
** Auto log-in for all unified wikis - OK
** Supersedes the xxBot log-in on w:en, which is now replaced by xx

* Log-out xx on any wiki, resulting in:
** Logged-out on all unified wikis - OK
** Fall-back to logged-in xxBot on w:en

Above implies that the appropriate bot, operating on multiple wikis - on most with an unified account (for very good reasons) - cannot operate anymore on e.g. w:en with the dedicated bot account.