LLMS_Template_Loader::maybe_redirect_to_sales_page()
Method: Handle sales page redirects for courses & memberships
Source: includes/class.llms.template.loader.php:94
LLMS_Template_Loader::restricted_by_course_track_prerequisite()
Method: Handle redirects and messages when a user attempts to access an item restricted by a course track prerequisite.
Source: includes/class.llms.template.loader.php:141