I just did two missions (two main, one sub) in chapter 2 resistance route but somehow the game advanced to the second half in chapter 2 already, despite there is still one main mission left. I also did the second sub mission instead of the second main mission however the game still advances regardless. Where the Leader greets the guildmaster to give you the final mission for chapter 2.
About drifter route, it has the most boss battle against major characters? Even if you have corruption level 3 upon ending chapter 4, the game still asks whether you'll stay in resistance or go to drifter instead of forcefully you into drifter?