On two different Discourse forums we run, the emails to the forum contact email address advising that there were posts which needed to be moderated (which were produced by the setting "notify about queued posts after) have stopped being sent.
They read: "Hello,
Posts from new users were held for moderation and are currently waiting to be reviewed. Approve or reject them here."
We last saw one on the 15th of September 2017 - the change may have happened after this date though as we don’t always have messages which need moderating. We have though had many messages since that date that have needed moderating.
These notifications are still appearing in the moderators’ inbox.
We are receiving other notifications by email, for example when there is a new version of Discourse.
We found the email notifications very useful so we would be keen to restore the facility.