CIPO,
I may be wrong on this one... but this is how I understand it.
There is no such thing as a single-engine CPL or a multi-engine CPL. It's just a CPL. You can then have either a single-engine class rating, or a multi-engine class rating, or both (as well as lots of other types of rating) added to that.
What many people decide to do is to combine their CPL skills test with their multi-engine class rating test. This is colloquially called a multi-engine CPL - but there is actually no such thing.
Since you already have a multi-engine class rating, you can't really do the test for this again. So your skills test will simply be a CPL skills test, regardless of what class of aircraft you do it in. Hence, no benefit at all in doing it in a multi, except for maintaining your multi currency.
I think.
FFF
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