They're building more KJ-500s based on the Y-9 airframe, I wouldn't be surprised if they produce another ten or more KJ-500s.
And I can expect a meaningful number of AEWC based on Y-20 eventually as well. But I think the Y-9 platform is acceptable to PLA as an AEWC carrier, so it might take a while for a Y-20 AEWC to emerge. I suspect it isn't very high on the list of priorities.
But I agree that the PLA overall should have 30-40 AEWC. Large ones like KJ-2000, medium platforms like KJ-200/500, but also a meaningful number of Y-7AEWC once it enters production.
Maybe something like 10 KJ-2000 class, 20 KJ-200/500 class, and another 20+ Y-7AEWC for carrier use as well as land based use as a lower maintenance, more flexible, "tactical" AEWC.