Recently a user on 4chan released 4 concept art from Rainbow Six, the person only specified these were old. We can only assume this is an early version of the Article 5 mission that takes place in a university based on Harvard in Rainbow Six Siege. It could also be from the canceled Rainbow Six Patriots, but a dev has stated earlier the only asset that made it over from Patriots was the Chalet map as far as we know.
In the concept art, you can clearly see it’s intended to be Harvard University and it shows several open areas where you could engage enemies.
We have reached out to Ubisoft for an official comment on these images.