There aren’t many devices out there with the Android Nougat so far. Other than the Pixel and Nexus lineup, OEMs are yet to push the update to their respective devices. With the Xperia beta program, Sony pushes out their latest software to a few users. This helps them iron out the kinks with their software before the full-blown release. The Xperia beta program was also used to ensure that the Lollipop and Marshmallow builds were delivered smoothly.
With the case of Nougat, Sony has been pushing out a Nougat build for the Xperia X Performance. It’s hitting a handful of devices across various regions, though not very widespread. Early reports indicate that the build comes with the October 1st security patch, a new version of STAMINA Mode and various camera tweaks like manual ISO adjustment and shutter speed. Essential features of Nougat like split-screen mode, redesigned notification menu are also present here.
Currently, there is no information whether Sony will push the beta out to more devices or when the official OTA will land. The fact that Nougat is already in beta stage is a good sign.