I think it is probably about engines, which are deliberately cut out. Could we get the original source of this photo?
Here's what I believe to be the
, or close to it. The poster's cryptic one-liner says "龙族新历程", which translates as "Dragon's new history" or "Dragon's new chapter" or something like that. I don't see anything special about the airframe itself, at least not externally. Of course, as others have pointed out, the engines are cropped out, so it could imply that this has something to do with the new engines (i.e. WS-15).
That said, the poster doesn't appear to be an insider or has any access to inside information. He's more of a CG artist and only occasionally posts actual photos he gathered from other sources. The image in question very probably came from someone else, but as to who that someone is or whether he/she also implied that this is a special airframe, I have no idea.