•David

Plan A would reintroduce a customs border but substitute electronic tracking of shipments for physical checks of goods.

Plan B would create a "new customs partnership" between the UK and the EU, and UK goods would be exported to the EU tariff-free.

The most recent issue of The Economist gives both UK customs models short shrift: neither will work, because (1) Brits aren't good at building IT systems and (2) the European Court of Justice has by EU law jurisdiction over EU customs, and that's a deal-breaker.