The best hour for sending an email newsletter is different for each of your subscribers. This is why NewsMAN made it possible for you to choose the option of sending your campaign at the hour when the recipient opens the most frequently.
Go to Newsletters > Drafts, click the details button of the newsletter you want to send, after choosing the list or the segment tick Use the best hour checkbox.
Schedule your sending for now or later, press Send newsletter to the whole list or Send newsletter to selected segments and confirm your newsletter.
If your subscriber has no best hour, he will receive your email at the scheduled hour.