Since Replicants very specifically have a four year lifespan doesn't this answer that question.
Side note; Harrison ford and one of the co-script writers believes he's human, he was a human in the original book, and Ridley scott director and the other script writer says he's a replicant
Most Helpful Girl
Sick, can't wait. HF has clearly aged. I don't think replicants age.1
Most Helpful Guy
How do you know it's the same Deckard? They could just make a new one every four years with implanted memories and make him look older so he believes he's human and aging...2