Installing handrail with returns

I want to install a wooden handrail on one side of a flight of stairs. The problem that I am having is on the top of the stairs I want to put a return, fastened to a stud. There is one stud directly above the top stair, and another stud 16 inches past the top of the stairs. So I either have to terminate the end of the return even with the top of the stair, or go past. What is the code for 4 steps? How far past the stair can a handrail go? Returns are a must on this handrail. I am only doing one handrail because I will have a wrought iron railing installed. I would never call a handrail temporary, but it will only be installed until a pro can do the whole job.