Since 2004, all models made in the CZ factory in Uhersky Brod have used a standard serial numbering scheme starting with letter A followed with six digits. The letter and numbers increased with each proofed/production item. Thus, there are no specific serial number schemes assigned to the P-10 models, CZ-75B, Bren 2, CZ 527, etc. which they used to have in the past. Your U+alpha+5-digits is the serial numbering scheme used for USA produced guns.
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