The reason you are confused is because there is no such thing as a "frozen ATPL".
The term is commonly used (especially in JAR-land), colloquially, to mean a CPL/IR, with passes in the ATPL exams. It sometimes includes an MCC too, depending who you talk to.
Under the JAR system, if you want to do a CPL and an IR, you can either do the CPL exams and the IR exams (and end up with a CPL/IR), or do the ATPL exams (and end up with a fATPL). There is absolutely no reason why anyone would want to do both the CPL exams and the IR exams - you will end up having to do a couple of exams twice, and therefore have more work to do. What's more, once you're ready to upgrade to an ATPL, you will need to do all the exams again. So the only sensible way of doing this is to do the ATPL exams - so there is no question that you should aim for a "fATPL" if you are going for a JAR license.
I don't know how this translates into the South African system, but I suspect it's not directly relevant at all.
FFF
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