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Continue to ChatThe airline has the right to substitute equipment, if you could book a 737 500, and you find out it's a 737 MAX, technically they don't have to honor your request. ... So you don't have a right to specify you are not going to go on a 737 MAX. - Mary Schiavo from https://whatsmyquote.com/quote/the-airline-has-the-right-to-substitute-equipment-if-you-could-book-a-737-500-and-you-find-out-it-s-a-737-max