The 170s will be done when they go for refurbishment either later this year or early next year. AGA are concentrating on the 156s, 153s and the MK3 stock beforehand.
As for the 360s, word is that they were painted in graffiti-resistant paint, which is incredibly difficult to paint over or remove (probably would require complete sanding down of the bodywork). So presumably they're at the back of the queue regarding EMU painting.