Noxus is as big as Zaun and really only Kled is updated for the new lore, so everyone would need work. Sion in that case might be left out simply because he actually HAS 100% canon lore. That'd be sad but at least understandable.
What I take away from this on Riot's end is that even though they might not get to everyone, they do at least know what's up with everyone in their regions. They couldn't really have done Warwick without figuring out the particulars of Singed, at least to some extent. They likely already had a bunch of stuff in mind for Twitch since his 2014 rework. It's gonna sound weird but those single intro paragraphs are actually a good thing here, because both Singed and Twitch have them, which assures me that Riot knows what's up with them even if their lore isn't updated.
So yeah, it sucks but it's not the end of the world. At least it's understandable, y'know?
On Ionia, I can imagine a whole bunch of champions might be missed off initially. Or done in groups. I can see them doing an update for ninjas specifically, doing Kennen, Zed and Akali together, perhaps done in the event of an Akali VGU. If they do Master Yi then Wukong's almost a given. In Demacia I can see them missing a few champs, but at least two are done for the new canon (Fiora and Poppy), one is about to be done for the new canon (Galio) and one probably doesn't need a whole lot of work anyway (Lucian).
