Oh man

I doubt Kanna and Hayato (because releasing Kanna without Hayato would make no sense) would come next summer. Mainly because that leaves no room for KMS's winter's update.

Again, other than hyper skills, there's been no real content being added during the gap between finishing Helisium and whatever KMS's next winter update. Spreading the Haya/Kanna update through February-March-April, leaving the Anniversay for May and filling up june with anything makes the most sense to me.

There is also that virtual world thing, but that'd be enough to fill up for a month at best.

Pretty much this^.

There's nothing saying we WON'T get Kanna and Hayato since we know how NEXON views something "exclusive".