We might be at 8 kj500 and 8 Y8q produced, currently. And given the pace of production, there might be several more added each year. While fo rY8q i see such a need, even for upward of 50-100 airframes, I do believe kj500 production will cease soon enough, as there's hardly an urgent need for 50+ AEW planes.
Considering the date when this satellite pic was taken (16/5/2017), I think we are probably at a total of at least 8 KJ-500s, and possibly 8 Y-8Qs.
And I agree, I wouldn't be opposed to drawing down KJ-500 production rate a bit and using those slots for Y-8Q instead. An annual production rate of 6-8 Y-8Qs would be a good rate of production to attain a core of ASW MPAs for the immediate future within four or five years for them to build on.
In the end I think the big limiting factor depends on what their annual Y-9 airframe production rate is. If they can only do like 10 a year then they'll be hard pressed to allocate slots reasonably. But if they can do 16 or 20 a year, that will open up a whole lot of opportunities to give themselves some leeway to build an operationally relevant number of aircraft of more than one type per year with a few airframes left over for more specialized missions.