Honestly I don't get this "J-16 = Su-30MKK-clone" like posted in such stupid reports (for example: Procurement: Chinese Counterfeiters Nail Another Russian Jet Fighter), since these all prove that these guys either can't distinguish a Su-27UB from a Su-30MKK, or they are intentionally posting bull**** or they are simply plain stupid. Propably their only source is KANWA !!!!
First of all; by simply comparing these "cell phone camera" images, which were allegedly showing the J-16, each one with at least a minimum of understanding can clearly see that this is a standard twin-seat-Flanker with the single wheel front gear, no IFR-probe and most noteable the canted fin-tips. (Just in comparison to a twin nose wheel gear, IFR-probe and sqaured tips of the MKK)
Therefore no need to discuss any further ...
Besides that as also noted, the question remains, what - if ever - is this mysterious J-16 ?? As far as I know this version will be simply a AG-optimised J-11B, which - similar to that strange behavior at Sukhoi, where each and every new Flanker received a new number - will propably feature the above mentioned features (similar to the J-15), but again so far we haven't seen that type.