With Google putting all its weight behind dark mode in Android Q, beta testers were a little miffed when they discovered that there was no user-facing on/off toggle for the mode. It was hidden behind an adb command, and everyone rushed to either set it to on or off. However, there was an auto value too, but it wasn't working properly. For some, it never changed between modes, and for others, it only changed once then stopped working. That automatic switch appears to be functional now.

Tipster Sergey reported to us that starting April 27, his Pixel on Q beta 2 began switching to dark mode at sunset, then light mode at sunrise. He had changed the adb command to auto (adb shell settings put secure ui_night_mode 0) earlier that month, but it never did anything until then. We were able to verify this independently on two devices. In the GIF below, you can see the time being changed from 8:36 AM to PM, then back, and the device's theme automatically switches along.

The cutoff time appears to be sunset and sunrise time, and this switch is independent of whether Night Light is enabled or not, which wallpaper colors you have, or whether Digital Wellbeing is set. Only the battery saver appears to override these settings, so if your phone's battery becomes critical before sunset, the dark mode will be triggered (just like it does when your device is set to the light mode). You can test it for yourself by following the steps here — just make sure you set the value to 0 and reboot your phone afterward.

We're not sure what caused the automatic mode to start doing its thing recently. At the moment, our sole theory is that it could be related to the Google app because version 9.78.3 beta (APK Mirror) rolled out to Sergey around the same time the automatic mode switch began working.