Razer Phone users who feel adventurous enough can grab the Android 8.1 Oreo preview for their handset, but they should be aware that this build will not receive any OTA updates in the future. Sadly, to install it, the bootloader must be unlocked, and this action would render the warranty of the handset void.
https://www.notebookcheck.net/Android-8-1-Oreo-preview-now-available-for-the-Razer-Phone.293610.0.html