OK, after a bit more digging, it does seem to be Brexit-related:
https://sellercentre.ebay.co.uk/news/brexit
New UK VAT arrangements for imports
On 1 January 2021, the UK government introduced a new model for the VAT treatment of goods arriving into Great Britain from outside of the UK. The new arrangements include the abolition of Low Value Consignment Relief, which relieves import VAT on consignments of goods valued at £15 or less. Online marketplaces (OMPs), where they are involved in facilitating the sale, are now responsible for collecting and accounting for the VAT. More details on these changes can be found
here.
...which led me to
https://brc.org.uk/news/trade/vat-1-january-brexit-guidance-for-businesses/
From there:
The UK Government published new guidance in late July for cross-border transactions involving VAT. Currently, during the transition period, the UK remains within the Common VAT Area, meaning goods sales between the UK and EU are not deemed to be imports and exports but intra-Union supplies or transfers of goods. The treatment for VAT of such transactions is markedly different.
The UK Government has agreed with BRC suggestions to restore the easement on postponed accounting for import VAT which would otherwise be payable by businesses. This easement will apply to all GB imports, including from the Rest of the World. So for goods imports of more than £135, the importing company will account for any import VAT due as part of their quarterly VAT return process. No payment will be required to clear goods at the GB border.
For goods under £135 in value, the point of liability for UK supply VAT will be at the point of sale not the point of importation. Online marketplaces, where these facilitate the sale, will be responsible for collecting and accounting for the VAT involved here, from 1 January. For business to business sales under £135, involving a cross border element, the VAT will be accounted for by the VAT-registered customer via a reverse charge.
With goods sold directly to consumers in GB without platform facilitation of the sale, the overseas seller will have to register and account for the VAT with HMRC.
Further information is contained in the HMT paper below. The BRC is continuing to liaise with the UK Government and the European Commission in terms of the operability of the rules in NI from 1 January under the Protocol, and with HMT in terms of the rules to be applied in GB.
https://www.gov.uk/government/publi...s-goods-sold-to-customers-from-1-january-2021
Well done Brexiters.
