No alternates don't automatically get in the next semester.. WCCD does not have a waiting list so you go up against whomever is apply that semester and if there GPA and points exceed yours they will...
I too am a student at WCCD... Last year 3 alternates got in. I met one of the girls last semester and she was number 3. So it is possible. I do know that if you don't get in you have to apply again...