It doesn't mean resignation so Orwin can gracefully exit. It doesn't mean retirement. It means HE'S FIRED!!! The only reason he is staying around until June is for the "knowledge transfer" which really shouldn't take more than about three minutes.
T Mr. Orwin, we're here for the knowledge transfer. What do we need to know about your job?
O: Okay.. well... you see that desk over there?
O: When I came to work in the morning I would crawl under the desk and hide. The other bit of information you need is the liquid in that large mason jar isn't apple juice. I never left until everyone had gone home and then I would sneak out through the garbage chute. Will that be all?
Orwin would be biggest bastrd ever found in Pharma Industry. First, his introduction in AFFY was through back door with some Hedge fund then he kept selling his shares, He did all that with calculations and intentional. No wonder he must be paid heavily from AMGN to follow the instructions.