Automatic Cache Cleanup?

In the FAQ on the ww.wp.xz.cn page for this plugin, there is the question: “Do you automatically clean up the cache upon website changes?” The answer is given: “Yes, you can enable this option from the settings page.” I am unable to find this option on the settings page of my recently installed version of Super Page Cache. Could someone give me more explicit instructions as to exactly where it is located?

Thanks!

The page I need help with: [log in to see the link]