Chinese aircraft numbering ????

I have a question regarding the Chinese aircraft numbering system for fighters: If You take a look at the numbers everyone knows the
J-5 (MiG-17),
J-6 (MiG-19),
J-7 (MiG-21),
J-8 (enlarged twin-engined development of J-7),
J-9 (Saab-37 look-alike based on the MiG-23) …. then the maybe newest Chinese fighter the
J-10 (Lavi-look alike with AL-31),
J-11 (original a Mirage F-1 look-alike) with it’s designation reused for the Su-27K,
J-12 (original a light fighter developed during the ’70) and it’s designation maybe reused again for the XXJ (???)
J-13 (original planed during the late ‘70as a J-6 replacement …. abandoned in the early ’90) and now sometimes reused for the Su-30MKK (???)
J-14 ….. sometimes used for a twin engined J-10-development or the XXJ ….??????

…. but why don’t have the also proposed East Wind Series fighters (Tf-104/-107/-113) have a J-designation and was there also another original J-10, so that the new J-10 (Lavi) reuses this designation … because of it’s development-timeframe it never fits as a J-10 into this order (J-12 would be much better !!!) …. and was there also a fighter based on the MiG-25 ????

Can someone help or does anyone have more information …

Best regards

Deino