I’ve tripped over myself a bit with this. 
I did not get the email from the first test (notify about queued posts after) because the Moderator inbox default is ‘Tracking’ and not ‘Watching’. You can change this default by going to /g/moderators/manage/interaction.
The emails I received were indeed from the second test (notify about flags after), as those reminders were sent as PMs.
Both seemed to work for ‘approved posts’ though.
I’ll go back and edit the other post (again). 