Javascript blocks access to a webpage

I have a homework webpage for my students, where I upload a new webpage for each class. Students click on a button leading to leitfile.html, which leads to a button linked to homework webpages for each week. Javascript blocks access to the webpage before the set time. The problem is that the webpage is not actually blocked, the link is just disabled. The web host is GoDaddy, it uses cPanel and Linux.Is there a way to prevent a webpage from being opened before the set time?

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