i'm no expert but i got a response yesterday as well. My response had a Scranton, PA postmark on it. Apparantly his fan club is located in Scranton according to the database.
anyway, i received 2 pics back and the one signature is identical to yours so i'm guessing it's autopenned. sorry. the weird thing though is that my second picture is also signed in a similar writing but not identical to my other signature. so maybe they give one original signature and autopen the rest? again, i'm a novice so i have no idea

hope this helps.