Awfully slow ( just 20 J-15 ) rate of production, don't you think?
It is no production rate. They build some, if they need some. Call it production on demand.
Now the task of the carrier force is to gain experience (a fifty-years-project, startet thirty-five years ago). The carrier force will be brought to usefull strenght for power projection later (in fifteen years), when it is ready.
In the 1980th the Chinese people were looking ahead and already knew, what they will need in the 2030th. That is impressing planning! And the carrier force will be ready in the 2030th. Remember all the people that told us, China can not run a carrier force. They can and they will be well prepared when the time is coming.