Not sure what the following means, but it was posted by a quite credible member of CJDBY (星海军事) on a thread talking about J-XY/J-15:
Link:
It talks about a certain "machine" (i.e. aircraft or related system) leaving the assembly line and preparing for final assembly (help needed for accurate translation). Could this be related to the upcoming J-15 upgraded variant or perhaps even the naval J-XY?
My interpretation is that a certain model moved from parallel production line to one single independent production line. Seems to be the J-15 to me because the J-XY couldn't have been on a parallel production line at this stage. Or better still, ask our own @Interstellar!