If your magazine should only be readable starting from a specific date and should expire after a specific date you can use the "Magazine valid" feature. You will need the AdFREE plan for this.
First go to "My Publications"
Then click on the pencil icon to edit the magazine
Then scroll to the "Visibility Settings" and check the box at "Validation". Enter the desired data and hit save.
Note: We're using the time zone Greenwhich Mean Time (GMT+0)