I was apprenhensive about making the ferry because of the need to line up hours in advance as recommended by the wash state ferry website. Now granted maybe the busy season has ended, but we had no trouble getting on the ferry either coming or going at pretty much the last minute.
We arrived at SEA at 11 got a rental car and drove up to make the 2:00 ferry. We arrived only 20 minutes prior but were able to make it. Leaving we had planned to make the 11:00 from Friday Harbor to Anacortes on a Sunday morning. We were told to be there at 8:15 just to be safe. We left our motel at 7:45 and I told my husband, "It's a long shot but let's see if we can get on the 8:05. We lucked out again. We had extra time to make our flight and stopped at the Chihuly Museum on the way. Anyway maybe it was a fluke (also the schedule changed last weekend from Summer to Fall) but we did good.