Making ships is nothing compared to wartime mass production of shells or ammunition. Where are the factories producing shells? It's going to cost a lot of money to set them up, and by the time they are up and running the war could be over.Are you saying Europe can make lots of carriers and frigates, but can't transition into making artillery shells even after 10 months?
I think they will continue doing what they have been so far buying up ammo from all over the world.