I always like to ask people if they have a moment to talk about our lord and scholar Joseph Campbell. I kid, but his work has been very influential to me in my personal life, and if there is an opportunity, I like to try and suggest that others read his work as well, or perhaps watch his interview with Bill Moyers on Youtube.
The idea of the Hero's Journey is that it can theoretically apply to any and all stories, if you break it down. Some of the pieces may be out of order or be missing entirely, but the same general structure applies. And this doesn't just apply to the entire story, acts, sequences/chapters, and even individual scenes. If done well, at least, they all start with some sense of normalcy, introduce a conflict of some sort, and then work to resolve that conflict. Comics are a side venture for me behind screenwriting, and so I love this stuff.
To actually answer your question, POST HOC definitely follows it, but it starts after the crossing of the threshold, as the protagonist was given life with a goal to accomplish. To be honest, the majority of the story will be Tests/Allies/Enemies.