Earlier quoted context omitted.
Source: I was the chief hw engineer for this product. Yes - the backlight temperature allows you to adjust it from a pure (albeit on the warmer side) white to pure amber.
Thanks very much for responding. You mentioned backlight, and forgive my ignorance, but is this type of E-paper not front-lit?
I think it’s like the kind of LCD you see on calculators and clocks and the original Game Boy, that doesn’t need a backlight to be visible but can have one