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HMRC internal manual

Customs Special Procedures Manual

Receipt into customs warehouse: over shipments

Goods received in excess of the quantity entered to the procedure must be regarded as dutiable and warehoused provisionally until the matter is resolved. Where the warehouse keeper wishes to enter over shipments to the customs warehouse arrangements, the entry declaration should be amended accordingly.

952/13 Article 173 Council Delegated Regulation 2015/2446 Article 148

If the warehouse keeper/depositor does not wish to warehouse any excess goods, the original declaration will not require amendment but an additional declaration to free circulation will be required to cover the over shipped goods (and the customs duty/import VAT paid as for a normal free circulation entry).