I'm guessing but, by putting in an LOI, their manufacturing slots are reserved but 2 things 1)BA won't have had to make a down payment as this isn't a firm order and 2) if Boeing can't recover the reputation for the Max sufficiently, BA can walk away penalty free.

There is no downside on this deal for BA.

of course, if they do walk and still need new aircraft, they'll have to join the queue for Airbuses.

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