Thank you for the links, the Washington Post did say that the boats had been
ordered along with the Club missiles. There is no evidence that the missiles were actually delivered.
Similarly, the GlobalSecurity.org link assumes that, in their words ‘...
Because China has access to the entire family of Russian CLUB missiles, the new KILO submarines that began arriving in 2005 could have the 300km-range 3M-14 land attack cruise missile ...’
My scepticism comes from the fact that the Indian boats (admittedly the 877EKM version) had to be modified to launch missiles.
Also from the rather lengthy report at this link.
Near the end of the piece they summarise the versions of ‘Kilo’ in 636 "Varshavyanka" they state that ‘several’ of the boats are equipped with Kalibr (not all of them).
There is a great deal of ‘cut and paste’ journalism which is often given more credit than it deserves.
You see the same wording in a number of different publications, all from a single source which is not disclosed. A photograph of a missile actually being loaded onto a Chinese Kilo would be evidence. Pretty much everything else is opinion.
As for new props and AIP wouldn't that make them a force to be reckoned with!
I also wonder if new battery technology is available like in the new Japanese boats?