Well it's 428 on a two class Boeing not 430. So that would be up against a 615 seat two class 380, burning an extra 3.6t per hour. So to an answer your question dropp it would need an extra 35 econ pax on board to pay for the extra weight. The other 150 can travel for free. It's 356 on the three class Boeing vs 517 on the 380 so only 126 traveling for free on that one.
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