Cope at max for this post, here we go:
On the brightside, another way to read this is: We're currently on chapter 4 and there will be 5 chapters total. When that ends, comes the dark route. He says that would technically be chapter 6. If we take it literally, then the dark route would be the size of a chapter (this could be wrong). Then comes the purity routes, which, by his decision of "I might just work on other projects at the same time" would probably mean that the purity routes aren't that demanding story-wise = story has basically ended.
So really we're close to the end of the main story (harem arc), where all things get set up I'd assume - then we have a single chapter of everything going down (dark route). Then we start getting a bunch of "but it could have ended this way instead" every two months. Until at the very very end we get all the answers to the puzzle with the true end.
What I mean to say is, obviously most of us will stick to the very end, but it would be conceivable that someone would just stick until the end of the first purity route and be able to go "yep, game's done, I'm out". So we should have at least some closure as the first purity route rolls out (which is much earlier than when the true end will).
