In a polyphonic cipher, two or more plaintext letters correspond to one ciphertext symbol.
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Also by hill-climbing. Rewrote my program in C, so it
converges in minutes (but needs a few tries to get close
to the answer).

Hello,

Can you confirm that the solution has 20 numbers from 0 to 9 (each twice) following the ordered alphabet ?

Or the length of it is 26 from A to Z with more twice for the "special" characters like J K Q U X and Z ?

Thanks for your answer

Hi vexilla72,

I've moved your question to the topic of the challenge in question so others can find it more easily.

Or the length of it is 26 from A to Z with more twice for the "special" characters like J K Q U X and Z ?

You should submit the key for this cipher as the solution.
This key consists of 26 digits where each digit represents the corresponding character in the alphabet. Due to the "special" characters considered equal, their respective digits in the key must also match.

Greetings, Bernd