We recently had a new post notification accidentally sent out to one of our subscriber lists. This got me wondering what exactly triggers notifications to be sent? I understand that at some level the subscriber controls settings (such as how often they receive posts) but when are these notifications "queued" so to speak?
As I understand it, it's any post added that has not already been seen by wordpress.com. So this would include any "new" posts even if they are added retroactively with past dates.
However, custom post types, page updates, and private or unpublished posts will not be sent out to subscribers.
Is this correct? If so is there anyway to confirm that a notification should be sent for a post? Or is it all just automagic?