OnePlus development team only presented OxygenOS, rather than the entire firmware. Moreover, there is still not known even the release date of the new firmware.
According to the Software-boom, OxygenOS is being tested now. It is expected that this firmware will be as simple as possible, without viruses, with only the most necessary software productivity and efficiency. The site OnePlus there is only one official screenshot of the firmware, and that section of the smartphone.
From this screenshot, you can find a version of OS Android (v5.0.2.), Which is based OxygenOS.
However, the Chinese media have leaked screenshot of the menu of the new system. As you know, the Chinese version will be called HydrogenOS and receive specific Chinese programs and services that are not relevant for us.
Perhaps this is fake. On the official screenshot icons charge clock signal, WiFi and mobile communications are in the upper right corner. The screenshot-leak their location and design are different. We doubt that the Chinese and the international version will be different design, but all can be.