The server hosting a web site is in Europe but the customers are worldwide.. So, which time zone is used to decide when to show the buttons? The local time zone of the visitor, or the server's time zone?
I believe that it should follow the Timezone settings of the Wordpress installation. However this does not seem to work correctly -- as the button as displayed outside of the times defined.

    tkalfaoglu Hi there, when you go to time schedules, you'll find 'Current timezone', it uses the timezone of the Wordpress installation.

    Can you check out what you see there?

    Example:

    a month later
    10 months later