Completely agree. In fact, I would like to see all subscriptions include a START date. Vote these ideas up:
The primary use-case is when we execute an single activity (like an email campaign), the marketers will want a report of all of the leads who engaged (clicked) with the email three days later. Without a start date, my team has to set reminders (or ask the marketer to remind them) on when these reports need to be sent. If the request is within a week of the campaign executing, you can get a bit creative and set the "Frequency" value to the day coming up; and set the "End Delivery" date to the day after the date it gets sent.
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