in two of my shipments it for some reason shows “Partial shipment”. In detail of that line I can see that there are multiple lines all with shipment size showing number equal to total.
So shipment with total=4 have 3 lines with partial shipments all showing size=4. Game actually put 12 cars to my inventory in this case.
In costs&inventory part my “on order” value show negative number of inventory when all is shipped.