I had quite a different experience. I did one exam then didn't attempt any others for another 18 months. Ended up with five passes but only a few weeks to do the two hardest exams. Rang CASA to ask about an extension and was told that they should be able to add a week or two (which wouldn't be enough as exams are only offered once a fortnight where I live) so decided I would have to do them all again. Then one day thought I would try ringing again. Got onto a different person and suggested to them that the record of the first exam be deleted and I would resit that in return for a longer extension. After some discussion about the long break after the first exam and the fact that I had been self studying (and deliberately not mentioning any personal problems that had hindered my study) he thought that sounded alright and I should put the proposition in writing to them (oh yes, and pay $150 to have it considered). After quite an effort to follow up the result I was very surprised but happy to have an extra 18 months added to the time and only have to resit Human Factors.