V1R,
The ATPL exam syllabus is basically a combination of the CPL exams and the IR exams.
As such, you can do the CPL course with either the CPL or the ATPL exams. And you can do the IR with either the IR or the ATPL exams. But if you want to upgrade your CPL/IR to an ATPL, you must have done the ATPL exams.
Very few people do the CPL exams. The reason is that most commercial pilots go on to do an IR. Doing the CPL exams and the IR exams separately is more work than just doing the ATPL exams, because there is some overlap between the two so you will have to do some exams twice. What's more, if you then go on to get an ATPL, you will have to do the whole lot again to get the ATPL exam credits - so each exam would be done either two or three times. For this reason, the only people who do the CPL exams are those who have no interest in getting their IR - mainly (but not exclusively) those who have retired from their day-job and are taking up instructing as a part-time job in their retirement. Because of the small demand for these exams, there are also not many places that offer the training for them (3 at the last count I think, but it may have changed since then).
Hope that answers it!
FFF
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