RGBW Control

Is it possible to control all the different chips red, green, blue and whites at the same time. I took a look at the developer API description but there was only RGB or color temperature modes available. These won’t allow me to control all the chips. Is the API description up to date?

The reason I ask this is because I would like to optimize the Yeelight RGBW bulb light quality. I managed to boost cheap (and bad) RGBW LED strip to around 95 CRI in my simulations done with Matlab. Currently there is no smart light product on the market that has high quality light and I know I can do that with standard red, green, blue and white LEDs.