PostNord is experiencing a force majeure under Swedish law, i.e a strike. I would think that the govt Transport Agency's exclusive contract with them provides an out with them in cases of force majeure to use alternate means, like allowing Tesla to pick up the plates from the factory or use a different carrier to deliver plates, since plates are mandated by the state and the Transport Agency is required to provide them by law.

Also it's one thing to refuse pickup, but PostNord employees are picking up the plates from the factory and then storing them at PostNord. The plates are definitely not the property of PostNord, they are either the property of the state Transport Agency, Tesla or the car owners. Accepting the package and then holding someone else's property seems a bit strange, especially given that these are not even Tesla's striking employees. I wonder how strong property laws are in Sweden.