Neopixelbus, unexpected behavior with SK6812 addressable LEDs

Hello all,
I am not much experienced with neither HA nor ESPHome. I am running the latest ESP Home 1.14.3. This is my second ESP board. I connected a test strip of 8 LEDs. The code used is:

light:
  - platform: neopixelbus
      variant: SK6812
      method: ESP8266_UART1
      type: GRBW
      pin: D4
      num_leds: 8
      name: "NeoPixel"
      id: neo_led
      restore_mode: RESTORE_DEFAULT_OFF

Everything works fine from the user interface. There are three sliders for the intensity of each color, a brightness slider for the brightness of the RGB part and a separate slider for the intensity of white. When I programmatic try to power it up with this code:

on_sunset:
    - elevation: 2°
      then: 
        - logger.log: "Elevation 2 triggered"
        - light.turn_on: 
            id: neo_led
            brightness: 20%
            white: 0%
            red: 20%
            green: 20%
            blue: 20%
            transition_length: 10s

everything works fine, and I get what I have put in the code, but if I give any percentage to white, white is started at 100%. My intention is to use white at 20% as a night light. I have tried these options:

brightness: 20%
white: 20%
red: 0%
green: 0%
blue: 0%
brightness: 0%
white: 20%
red: 0%
green: 0%
blue: 0%

With both I get 100% white, when the event triggers.

The fallback option is to use some RGB white, but the intention was to use white as a night light and the colors for other needs and mood lights. Any help, or idea would be apreciated.