Changes introduced in CDS release 5.2.1 – AEB Help Center

HMRC have introduced the following changes in CDS release 5.2.1. Release date 30 July 2026.

Please note: Due to the changes introduced in this release, there may be an impact on pre-lodged declarations. Any pre-lodged declarations that will arrive on or after the release date, that will be affected by the changes in this document, will need to be amended to be compliant with these changes, or the declarations will be rejected.

Updated codes can be found at the following link: https://www.gov.uk/government/collections/uk-trade-tariff-volume-3-for-cds--2#combined-appendices
If these changes impact you, please check your templates and update them accordingly.

CDS change	Movement type	Declaration completion instructions
New error code message for Procedure Code / Additional Procedure Code relation errors	All	A new error code is being introduced for when a Procedure Code (PC) and Additional Procedure Code (APC) combination is invalid to indicate that the issue lies with the PC/APC combination. This new error code will cover cases where: A PC requires completion of a specific APC that is not included on the same goods item. An APC has been included on a goods item that is not compatible with the PC declared on that goods item.
New Additional Information (AI) Code	Export	A new AI Code ‘BCPEX’ has been added to the CDS Code List. This code should only be used when instructed by HMRC. Please see Appendix 4B for Completion Instructions when declaring this AI Code in Data Element (DE) 2/2.
New Document Codes	Import/Export	Document Codes ‘C127’, ‘C128’, ‘C129’, ‘U190’, ‘Y081’, ‘Y682’, ‘Y683’, ‘Y684’, ‘Y685’, ‘Y763’, ‘Y770’, ‘9L51’, ‘9Y17’, and ‘9Y51’ have been added to the CDS Code List. Please see Appendix 5A for full Completion Instructions for these codes.
Amendment to Document Code ‘C001’		The Declaration Completion Instructions for Document Code ‘C001’ have been updated. Document Status Code ‘IA’ has been added for use with this code. Document Status Code ‘XX’ is no longer valid for use with this code. The Document Reason field no longer needs completing when using this code. Please see Appendix 5A for full Completion Instructions when using Document Code ‘C001’. Failure to declare the code correctly will result in the declaration being rejected.
Goods Location Codes	All	New Goods Location Codes have been added to the CDS codelist. Appendix 16 will be updated with the details of these GLCs ASAP after the release.
Northern Ireland Movements	Import/Export	The feature introduced in Release 5.2.0 that prevented certain Authorisation Types from being declared on Northern Ireland (NI) declarations will be reverted. This feature was Item 7 in the release 5.2.0 guidance document and will no longer apply after the 30th July. Following the reversion of this feature, the system behaviour will return to its pre-4th July state. Authorisation Type Code ‘MIB’ will not be allowed on export declarations from Northern Ireland where AI Code ‘NIEXP’ has been declared. If Authorisation Type Code ‘MIB’ is declared in DE 3/39 and ‘NIEXP’ is declared in DE 2/2, the declaration will be rejected.