Moodle Dates in Edit Settings
Course visibility determines whether students can access the course. If it is set to Show, no matter what the Course start date is, the students can access the course. If it is set to Hide, no matter what the Course start date is, the students cannot access the course. Course visibility overrides Course start date for student access.
Course start date determines how the course displays in students' My Courses link. If the Course start date is in the future and the Course visibility is set to Show, the course will be listed under the Future category. If the Course start date has passed and the Course visibility is set to Show, the course will be listed under the In Progress category. If the Course visibility is set to Hide, the course will not display under My Courses at all.