When you are better prepared for Brexit than the UK.
“Neighbouring countries including France, the Netherlands and Ireland launched customs officials recruitment drives last year, with six-month training schedules considered a minimum”
https://www.theguardian.com/politics/2020/feb/28/extra-50000-border-staff-needed-for-post-brexit-trade-says-gove

Fri Feb 28 13:21:08 +0000 2020