Okay I think the most likely place (and the most convenient) place for the Red chapter is the slot between HGSS and BW. Red doesn't appear at all in BW (and it's just a cameo in BW2 and it wouldn't really be a "special chapter" at that time because more previous characters appear there). Red appears in the HGSS games and his appearance in the manga was limited to a cameo so I think he will get a little bit of screentime while it's still relevant. And a Red round wouldn't fit in with any Gen V chapters and Kusaka will probably want the Red chapter to fit in somewhere so it will probably be an interlude (or epilogue). It happened before with the Green and Silver escaping round so it may happen again here. And I hope all the other Kanto dexholders get at least one scene.
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