Will MTMTE revisit in some fashion the Functionist timeline? what with Rung possibly being a key for something nefarious.
Seems likely, what with the briefcase existing and the timeline confirmed to exist. When, who knows, but at some point.
If Roberts had no intention of returning there, then he probably wouldn't have established that the timeline/universe continues to exist and that they figured out what Rung's alt mode is. So as long as he remains on the book, I'm certain it isn't a matter of "if" but "when."
I think it will definitely happen, the real question is if we will simply get another story in that timeline, or if it will someone interact with the "main" universe. Much like the Mirror Universe in Star Trek, it's a reoccurring element, but it rarely has any real consequences on "our" main universe.
I hope so. I'm itching to learn more about Rung and his movement. Like, is he straight up a resistance leader/fighter or did the movement form around him as just a figure head. I think Other!Rung would make a good villain.
I don't know about that. For all we know Runh's alt mode might be a portal between dimensions or something.
I reckon the Functionists are tied in to all this cogwheel-glyph business and are what the giant spark was trying to warn Skids about.