Here it is, uploaded just past midnight on 2019/02/03 Beijing time. She has a deeper voice and sounds very unlike most Chinese vocals. The song is a cover of "徒劳的爱之美少女 (Futile Love of the Beautiful Maiden)", one of the tracks on Xingchen's first album.
While they didn't confirm it anywhere, it's pretty safe to say she's an UTAU. She lacks any of the qualities of VOCALOID, CeVIO, Sharpkey or Synthesizer V.
What do you think of her voice? Are you excited to hear more?