2close,
The ATPL theory exams allow you to start training for both the CPL and the IR within 3 years of passing the final exam. They also allow you to upgrade your CPL to an ATPL once you have the necessary experience. (There is a requirement to not let your IR lapse by more than 7 years if you want to do this, too, but I don't think that's relevant to the question.)
The CPL exams, on the other hand, allow you to start training for the CPL only. If you subsequently want to do an IR, you will have to do either the IR or the ATPL exams. If you want to upgrade the CPL to an ATPL, you will have to do the ATPL exams. This will result in you having to do some exams two, or even three, times.
If there is even the remotest possibility that you may want to do an IR within 3 years of completing your exams, then do the ATPL exams. Otherwise, the CPL exams will be sufficient.
As for the schools which offer the CPL course, the complete list is
here. From memory, I think there were only one or two schools that offer the course, and only by distance learning... but Adobe Acrobat is playing up on my PC so I can't check that right now.
FFF
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