I got the dates with question marks from your previous table.
If the first flight did take place in September 2023 for J-31, it could be possible there might be 2 other prototypes already built for static load and flight testing.
I'm basing my assumptions on how quickly the first 3 JF-17 prototypes were built and put to tests. Totally guess work at this point.
31-05-2003 PT-01 - Flight Performance Prototype
FC-1 / Super-7 Designation
- 31-May-2003 - Roll Out
- 27-June-2003 - Low Speed Taxiing
- 25-Aug-2003 - 2 Maiden Flights
JF-17 Thunder Designation
- 2-Sept-2003 - Official Maiden Flight with JF-17 Thunder markings
??-??-2003 PT-02 - Static Load Test Prototype
09-04-2004 PT-03 - Flight Performance Prototype