While we’re talking about objective characters changing, I had a bit of a revelation in this regard recently. So here’s my example: Imagine a character serving an evil Empire–let’s call him Cecil. He has an ally who Helps him game the system, Tempting him with the ill-gotten gains of corruption and tyranny–Lilith, say. (Note that’s she not the IC.) At the start of the story, while Cecil is still fully under the sway of the Empire, he primarily sees Lilith for her Help component, so her primary role appears to be the Guardian. But as he goes through his arc of redemption, he begins to see the true monstrosity of the Empire, and in the same way, he begins to see Lilith’s true nature, how her Helping was really undermining him through Temptation. Now we see her primary role as the Contagonist.
All this to say, perhaps objective characters don’t change, but as the story develops, different aspects of the characters shine more brightly.