You have the opportunity to "show" or "hide" each of the individual tracks you have set up for your gym. Not sure what a track is? See What Is A Track? for more information.
First, from the gym admin menu in the header, click the Programming Tracks link. The Programming Tracks page displays each of your gym's tracks and gives you various display options for each.
You can control when workouts on a given track are revealed on members' CrossFit btwb calendars via the Future WODs column. Setting a track to "Show" will display all workouts on that track via members' calendars, including all future workouts. Setting a track to "Hide" will apply the preferences set via the Edit Prefs gym admin menu item.
For more information on setting the exact time workouts on a track are revealed, view Can I hide planned workouts from members?