Final answer:
Sitecore will automatically publish content at a specified time if publishing restrictions are set up with correct dates and times, assuming the server and configurations are properly set for automated tasks.
Step-by-step explanation:
When setting up publishing restrictions in Sitecore, you can specify when the content should become available or be removed from the live site by setting up publishable from and to dates in the Restrictions section of the Publish tab. If you set a specific scheduled date and time for the content to go live, Sitecore's publishing service will automatically publish the content at that time, provided that the Sitecore server is running, and the configuration is set correctly for automated publishing tasks. It's important to ensure that your scheduling tasks are properly configured and that your Sitecore server's time settings are correct.