Notifications for task updates not sent to assigned users/team when project is in Planning

When a project status is "Planning" and a user or team is assigned to a task, and an update (comment) is added to that task, the assigned receive an email notification. We would like them to only receive a notification if they are specifically tagged. Our project managers like to add notes that will be relevant when the project is Current, and do not want anyone alerted to these updates beforehand.