SolvedCDSSG04540 | Navigating the Tariff, Step 5 - Identifying Union v National Additional Procedure Codes
From HM Revenue & Customs · Customs CDS Volume 3 Tariff, Step-by-Step Guide
Import and Export Additional Procedure Codes are separated into two lists.
Codes beginning with a letter that are referred to as Union Codes
Codes beginning with a number that are referred to as National Codes.
Union Codes take precedence and must always be declared first on the customs declaration.