During the rehearsal, trucks crossing into France from the British side had the bar codes of their customs declarations scanned by a Eurotunnel agent, a formality that will become systematic once Brexit takes place.
“We are confident of our capacity to assure the smooth flow (of traffic) through the terminal, just like today,” Eurotunnel spokeswoman Anne-Laure Descleves told AFP in Calais, the transport hub on the French side of the tunnel.
Eurotunnel runs the shuttle trains that take vehicles through the Channel Tunnel between Calais and the English port of Folkestone.
British Prime Minister Boris Johnson has pledged his country will leave the EU on October 31 — with or without a divorce deal with the bloc — though many analysts regard this as far from certain.
Descleves said the key task was to make clear to transporters that they had to fill out a customs declaration online in advance in order to obtain the bar code and complete the customs formalities.
Once the code is scanned, the contents of the load being transported will appear in the systems of French customs agents, who can the decide whether to carry out additional checks or a search.
Capacity at the terminal has also been expanded to stave off the threat of heavy queues among the 5,000 heavy goods vehicles which cross through the tunnel each day.
“The Channel Tunnel will not be a traffic bottleneck,” Descleves said.
The regional director for French customs, Eric Meunier, also said he was confident his teams were ready after some two years of preparations.
“The 'digital border' is something that has been complex but that finally works today. This is what we are testing with drills. So we are confident because we are very prepared,” he said.
Despite the preparations, however, some truck drivers are still bracing themselves for long queues.
“It's going to be a lot of waiting, a lot of checks, a lot of waiting on both sides — thousands of trucks, queues, hours of waiting,” said Steven Meurin, a truck driver for the RDV company.