Pro Forms Nestable - Courses question

Hi, I’d like to know if it would be possible to make two nestable values. To explain, I have a CPT Courses and in it I have metabox groups for different sessions during the year.
So I’d like to be able to choose the course I want to register for from the list of my posts (so far so good), but below that I should be able to choose the session.
Basically, I need to be able to select several courses with one session.
Is this possible, Daniele?