Auburn has a new SID. The Auburn one departure went into effect a few days ago. I know SEA center computers are not adapted to the departure yet so as of now they are rejecting them. I'm not completely sure how DUATS works with rejected flight plans from center. But you can always put in remarks that you want the Auburn One and when getting your clearance request it. Also, if you call Flight Service and get a briefer outside of SEA you might want to tell them to put it in remarks because they probably wont know that it’s non adapted.