As long as the Office know what paperwork is required, when the lad flew out to his ship he normally flies from Teesside to Amsterdam and then wherever in the World his ship is, this time it was in Singapore after a Drydocking, when he arrived at Teesside he picked up his Office arranged tickets from the desk showing the end of his journey would be Singapore, however when he got to the Boarding Check In they asked him for his Landing Pass for Singapore (now required due to Covid-19) oops no, "well you can't board the aircraft", phoned his Office in England they knew nothing about it so his journey was delayed 24hrs. Good job his ship had not sailed in the meantime.
I have no doubt that in the Dover situation the French will either go on a go slow or even go on strike so that Macron can blackmail us for more money, the British Taxpayer has already paid a fortune for security fencing around the Port of Calais.