Ok so we can agree on this
CV-16 is 001
CV-17 is 001A for whatever reason (A is next iteration I guess)
CV-18 is 002
What's 003?
001 is a design project number. CV-17 is clearly close to being a copy of Kuznetsov derived 001 design, hence 001A. It seems unlikely to me that the 002 design following 001A would be a one off design. There is advantage to two similar ships operating in pairs. Most likely 002 would consist of at least a pair of hulls, so CV-18 and CV-19 will either both be built to the 002 design, or one is 002, the second slightly improved 002A.
Unlike the US, whose basic carrier design was stabilized by late 1960s, following trial and error through bringing 4 incrementally improving post war carrier classes to services, thus facilitating a 11 ship run of very similar design (1JFK fossil fuel class, and 10 otherwise almost identical nuclear Nimitz class), the Chinese carrier design will likely need several more incremental classes before settling down on definitive design, so I expect 003 will be the new design for CV-20, following 2 002 hulls.