I'm not a huge fan of the way those cryptic comments where put out onto Twitter as if they possibly could be referring to J-35.
Because:
1. It is so cryptic, it could mean J-35 or some other aircraft. Without a high degree of confidence, preemptively oversharing reduces the long term credibility of PLA watching in the larger military watching sphere at large.
2. Even if they are referring to J-35, even if they referred to it by name, it is still not particularly noteworthy unless they explicitly gave a date and time (or ideally showing footage of it) of some sort of milestone, because that sort of soft teasing is also just more unnecessary buildup for an aircraft whose role, intent and platform deployment that is widely known and not a matter of debate. No reason to share information unless there is legitimate interesting news.