Hello there, @5gray ...
Sorry to see that your question has been sitting out here since early August without a response. I know that you can associate many courses (think of them as the "child" courses) with one course that is designated as a "blueprint" course. But, I'm not sure about multiple blueprint courses. Can you please describe the scenario in which you'd be syncing two or more "blueprint" courses with a single "child" course...if I'm interpreting your question correctly? Thanks!
It is not possible to have a course associated with multiple BluePrint courses. It's also not possible to "next" Blueprint courses by having a Blueprint course be an associated course of another Blueprint course.