First example i have seen with the "pintail" lugs and CIOCC piercings in the lower headlug and BB shell, so I'm a believer now that the Pelizzoli shop made THIS one, or at least the Bonati shop did using old stock lugs and shell.
But I dispute whether Billato was the shop that built the later Concordes: might have happened but I think more likely this gets repeated cause someone once confused one "B" shop (Bonati) with another (Billato). It was Bonati that bought the CIOCC brandname as well as "John" brands from Pelizzoli and also made the Conti brand. I think they built some Battaglin as well as some Guerciotti frames, too.