Question about visa for Hainan

In case that you obtain a Chinese tourist (L) visa you can travel throughout the mainland China practically without limitations. You can, of course, travel to Hainan and the travel to Hainan is the same as the travel to Shanghai, Xiamen or Xi'an. Hainan is part of the mainland China and your flight or train travel there is purely domestic. You will not be asked why do you travel there nor you will have to deal with any agency. Also, you can return back to the continent again by air or train and also in this case, you will not be asked anything.

Your friend with a valid Chinese student visa is also allowed to travel to Hainan and back without any restrictions. Hainan is and remains a destination where Chinese visa holders can travel in the same way as they travel to any mainland Chinese continental city.

Don't worry, you are perfectly fine with your actual visas.