According to the CNN Politics article, "Bao Bao will fly nonstop from Dulles, Virginia, to Chengdu, China, in a large crate aboard the custom-decaled 'FedEx Panda Express' 777F aircraft. She will be accompanied by a keeper and a veterinarian."
That means it will be a charter, which means it was put in open time, immediately frozen, and at the perfect time was unfrozen and picked up by ... well, we all know the rest.
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