I don't think a change to 24V is doable like that, even if the parts theoretically support it - it'll be at a different efficiency point (= also thermal issue)

I don't think a change to 24V is doable like that, even if the parts theoretically support it - it'll be at a different efficiency point (= also thermal issue) for one, but also the regulator feedback loops might become unstable without reengineering.