It depends on the Russian Engines. Without it, your stuck with current 4. prototypes.
Actually that's an interesting issue. They have so far received at least 10 RD-93 out of the 100 that they signed. We know they were originally suppose to get 15 last year and 20 this year, so the question is whether they have received more. So, outside of the first 4 prototypes, they can theoretically build more than 10 JF-17s. Another question is what the Russians are going to do now that the engines are going to PAF JF-17s? Cut off the supply? It's an extremely interesting development from what I can see.
Does the PLAAF even want this aircraft? It already has the hi (J11) and low (J10) aircraft mix.According to this.
The original plan was to make 400 fighters, of which Pakistan will buy 150 and China will buy 250.
I'm not sure if that is any different from other earlier plans that I have heard.