Pretty sure they're different. That pylon for PL-12 looks similar but is noticeably longer, and its model number begins with 'PFT12[....]' -Indeed interesting, but not truly conclusive... isn't this the same pylon here on a J-16 carrying a PL-15 (top) and a PL-12 (bottom)?
View attachment 115844
View attachment 115843
Whereas the pylon for PL-15 is this -