Integrated is responsible for providing the right articles to exporters (http://www.integratedfordevelopers.com/content/documentation/article/creating-an-exporter-for-content-distribution).
Currently, unpublished articles are exported as well.
Check for isPublished, when false export the document the "delete" state instead of "add" state
Note: articles published in the future will have a "delete" state as well, issue covers this scenario.
This happens in vendor/integrated/integrated/src/Bundle/ChannelBundle/EventListener/Doctrine/ChannelDistributionListener.php.
Insert (prePersist) and update always have an add state. Should be expanded with the check in the issue.