What happened to the J-6s?
There were rumors that the PLAAF was working on turning the J-6s into drones. There were even talks about how swarms of such drones can occupy the adversary's air defense systems for the manned strikers to go in safely. I think so far there has been no such "J-6 based drone" spotted though.
Was that rumor just a fanboy fantasy? Or was the project cancelled early on?
It's real ... they were converted to B-6 UCAVs
Around 200 retired J-6/Mig-19 fighters are thought to have been converted to UAVs as B-6 (J-6W?) drones. The aircraft had the wing-root 30mm guns, ejection seat and other life support systems removed. New remote flight control, navigational (?) and fire control systems including datalink were installed. They are believed to have been stationed in Southeast China facing Taiwan (S/N ). Some s are seen carrying two 250kg bombs under the wings, suggesting their role as low-cost ground attack UCAVs, or as cruise missiles or decoys to probe, disrupt even suppress enemy air defence systems. Therefore the guidance system might include passive radar homing for anti-radiation missions. It was rumored that a further has been developed with the cockpit completely removed. Depending on the cost, B-6 could be modified to fly additional missions including ELINT, ECM and laying naval mines.