canon ("The Main Story"):

homestuck, the epilogues, beyond canon, hiveswap

apocrypha (sideworks that are inspired/informed by main works):

friendsim, pesterquest, paradox space, frafworks, skaianet systems, someeee fanworks like "detective pony" because it gets a direct shoutout in bc... maybe stuff like hussie commentary + formspring answers??

fanontinuum(?):

everything else?

also, may i suggest something like "metacanon" (or... i guess "the canontinuum" could also work) as the concept of canon within the work. cuz this is the basis of the conversation, right? discerning the real world concept from the fictional one? like how there is andrew hussie, real person, author of homestuck, and AH, the megalomaniacal self-insert character in the webcomic homestuck. "postcanon" and "dubious authenticity" feel like fictional conceits rather than real world ones.