Hi Ryan,
If the goods are being imported in to the UK then the VAT will become due once the import is made.
The supplier will have to check the time of supply rules regarding their export from the EU with their member state.
However, if you become the legal owner of the goods in the EU then essentially you will be paying a deposit to the EU company for a domestic sale in the EU which will attract EU VAT at that point.
Once you import the goods in to the UK there will be UK VAT to pay at the border which you can recover subject to the input tax guidance below.
10. Introduction to input tax
Thank you.