My father was in the CCC in 1939 and again in 1941. I don't remember the time element, but you were either in for 3 or 6 months. After you get out you had to wait a certain amount of time before you could re enlist again. Probably to give others a chance to enroll who haven't had the opportunity. My father first duty was a camp in S.E. Louisiana where there was cut over piney woods and they had to fight brush fires. In his second enrollment he went to Mt. Lassen Park to clear trees to build roads.