They have not paid for them yet, that is $300 million it still has to pay up if it takes on all 4. Also your figures are a little off TOTAL backlog is $390 million for 4 contracts combined , that will be just enough to cover the cost of the ships in the first place, and my maths makes it unlikely they will be able to purchase all 4 in the first place unless they want to $200 million in debt with no cash on hand.
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