This is great! A couple follow-up questions:
1) Where would you recommend this code go so as to show up after the content in my timeline_event post type single posts?
2) Do I need a GeneratePress hook as well? If so, I would need help writing that function
3) What would be the best way to do this multiple times on the same page? Since I have both the timeline_tag and the timeline_category posts that I want to render out, is there a way to hook them both into the post after the content?
I wish I was better at PHP for moments like these.
Thanks Tom