Hi Piotrek,
That does not sound like any JAA alternative test I have heard of and think it may be a national test (Poland only) which would only apply to Class 2. It may be accepted by the Polish aviation authority for Class 1 but you would have to ask them.
I doubt the UK CAA would accept it if it is not one of the JAA approved types of test but so what, get your CPL in Poland. It is fully recognised as a JAA member state and the licence would be valid everywhere.
I would be very interested to hear more details of the test.
All the best,
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