The mailing module gives you access to the mailing queue. You can monitor all scheduled emails in the queue and check their status. The queue list can be filtered from the panel where you can select dates and date type.
Clicking on a row in the table containment the queue entries will give you more information about the entry. If you click on the + sign at the first column you can see the transactions attached to the queue entry.
You can delete mails from the queue or send them earlier.
Mails can be scheduled from the mailing module. Click Compose email button.
There is a cron job running on the server every minute that check for mails to be send. This functionality can be manually execute by the button Run now
CRON JOB scheduling
/server/cronjobs/MailQueue.php executable (chmod +x). cronjob -e and then * * * * * php /home/www/__PROJECT_NAME__/server/cronjobs/MailQueue.php