I’m using CF APO on WordPress with CF plugin, when the page is split using Page-Links <!--nextpage-->, the APO cache only purge the first page, sub-page is not purge.
I wouldn’t call it a bug. I believe that APO relies on WordPress to tell it which pages need to be purged. I could be wrong. It’d be worth opening a ticket to let them know: support AT cloudflare DOT com. Be sure to provide a link to this thread and to the affected page/post on your site.