Just Flight has been showing off a few previews of the upcoming Concorde for Prepar3D, developed by DC Designs. The plane is still in development and you may spot things that are still lacking, such as PBR textures. The team confirmed these are still to be added and the exterior model is still being tweaked before being ready to fly in our sims.
A few days ago, the DC Designs team also shared their future plans and roadmap. The team confirmed that the Concorde is still scheduled for release in September, after which the company will shift their focus to Microsoft Flight Simulator. The Concorde is scheduled to be released for MSFS later this year. You can read the full roadmap here.