It looks like the Pixel-exclusive Hold for Me is finally making its way here. This feature lets you use Google Assistant on your phone to hold the line until you're ready to speak or answer. It will stay on the line until a human being is detected on the other end, so you don't have to suffer through call hold music. Some Pixel owners in the country are now gaining access to the feature.
Hold for Me is powered by Google Duplex, the AI system that lets Assistant make appointments and check store hours over the phone for you. It works for Pixel models starting from the Pixel 3 until the Pixel 5. But it looks like the Android 12 Beta has been a precursor to activation on their devices, and the Google Phone app beta version required is 70.0.3.394259711.
Source: 9to5Google