Who says that Nexus owners get to have all the fun? Yesterday an innocuous XDA thread claimed to have a beta version of an Android 7.0 build, ready and waiting for Huawei's dual-camera phone, the P9. Usually that sort of post when we're still weeks or months away from a full AOSP release of a new Android version is, to put it bluntly, bunk. But in this case, users who have flashed the ROM say that it's functional and apparently legitimate - Huawei's proprietary EMUI skin, marked as version 5, is running on top of Nougat. It's working on the EVA-L09 model; others may not be compatible.
The build posted to XDA can be flashed to stock, unrooted, bootloader-locked P9 phones via Huawei's Dload tool. It appears to be an update file, not a full system flash. If we take this ROM at face value, it looks like Huawei's software developers are working with the open source code already available in AOSP (the starting point for the Developer Preview/Beta builds already seen on Nexus devices and the Pixel C). That means that they would need to update it to the final build once Nougat is publicly available. Updates to the P9 (and any other Huawei phones with internal Nougat betas) wouldn't be instantaneous, but they could come to users in a matter of weeks instead of months.
The initial link seems to be overloaded, but later posters to the thread have uploaded copies. There are a few teething troubles with the beta ROM, including issues with the Play Store and Amazon Appstore. Some users have been able to downgrade to an older version after a full wipe, but if you want to make sure you get over-the-air updates in the future, it's probably a bad idea to flash non-public software. By the way, Huawei isn't the only company working on Nougat betas: Sony has one for the Xperia Z3, which they released publicly.