OnePlus in China will be holding an event on the 7th April where a new version of the companies Chinese ROM will be unveiled.
OnePlus has two ROMs for its phones. Hydrogen OS is their Chinese ROM with a custom UI and no Google services, while Oxygen is the international version which is pretty close to a stock Android install.
An event being held in Beijing on the 7th April has now been confirmed to be about a new Hydrogen OS launch for the Chinese market which many believe will see OnePlus move on to Android 6.0 Marshmallow.
Previously it was rumoured that the April event could have been the launch date for the OnePlus 3 that has recently been seen in Antutu leaks. OnePlus revealed that this wasn’t the case, however the Antutu results did confirm the OnePlus 3 (A3000) will come with 4GB RAM, 32GB storage (SD support also) 1920 x 1080 5.5-inch display, 8 mega-pixel front camera, 16 mega-pixel rear and Android 6.0.1.