How non-flex are these orders? Oftentimes one reads of some airline or the other cancelling orders due to funding, economy downturns or the inability of the manufacturer to stick to a schedule.

The cynic in me suspects the large initial numbers get both Boeing and Emirates the desired publicity and shareholder approval. Later these orders probably get toned down a bit. What's the delivery timeline on an order like this? 10 years? I suspects no one knows the future of an airline that far down the line, not even Emirates.