Well I was a bit impatient and my boy took the CGC when he was 5.5 months. He failed in the the most spectacular fashion. He sat on a lay and laid on a sit. He twirled for a stay and crawled for a come. He was having the time of his life and putting everyone in stitches. Needless to say we will be retaking it.
Our local dog club instructor advised, once she could finish wiping the laughing tears from her eyes, that most shepherds she had seen seemed to be better taking the test at or after 1yr of age. We'll be waiting till after his first birthday to try again. Lord only knows what tricks he'll have up his sleeve by then.