AS far as I know, Project 310 is the code name for Shenyang's stealth fighter( Just like Project 718 for Chengdu's J-20 ). They paint "31001" on the first prototype might indicate the fact there is no official endorsement on this project yet. Anyway the bird is unlikely to be called J-31 in any cases.
BTW, rumor says there are 3 more stealth planes under development, and the "red B2" is not among them.
That I definitely agree! I had a big problem calling it J-31 and thought we shoud stick to J-21 or F-60. But everybody adapted so quickly. I thought to myself "Oh to hell with it. I'll just go with the flow..."
Now this Project 310 thingy, I saw it this afternoon over on the CD but wasn't sure whether it was just someone's wild guess or it really is.