You’re right. Apparently you liked the film even more than I did and remember more of the details. But aren’t replicants just an advanced form of androids? The original story was titled, “Do androids dream of electric sheep?”.
Roy Batty (the Rutger Hauer character) and his colleagues were not androids or cyborgs or clones, but were human-engineered biological entities, ‘grown’ from scratch, although some parts were subcontracted (like to the eye-guy). They were also ‘grown’ with an internal self-destruct clock. They came back to Earth, risking automatic execution if caught, in the hope of finding a solution to stopping that clock. (Obviously the movie made an impression!)