Note: Mass emails sent from the Smart CRM can only be sent to 250 contacts at a time. 
To mass email all contacts (or 251+) use the Schedule instructions below and "Send to Contacts with Status:" select all statuses
To schedule a mass email (or to email all/more than 250 contacts)
1. Go to Marketing → on the Marketing screen, find “Scheduled Mass Emails” and click on the “Get Started” button

2.
Click on the green “+ Schedule Email” button on the top-right

3.
On the pop up, select recipients, time and date, template (optional), and fill the subject and message → click on the “Schedule” button