That's called problem transference, and is one of my greatest frustrations in business and life. You have a problem, so instead of resolving it or predicting/planning it out of your process, you transfer it to your customer. I don't have a part, so now I can break my commitment to you, so now it's not my problem, it's yours. Same goes in life, I get stuck in traffic, call work and tell my boss I'm running late and that he'll need to put off the meeting, so now my tardiness and lack of planning is his problem, not mine.They shipped 61 - and said they could have done 2 more if it wasn't for the part issue. Presumably they thought they were going to get parts in a day or so, that could have let them ship just before 31st. Also, it means that these two are substantially complete.
Best way to avoid problem transference? Manage customer expectations through running your operation with the necessary contingencies to meet your commitments regardless of any but truly and absolutely unforeseeable disasters. When did Bombardier know they were missing components? Did they try to fly the parts in? Did they not have contingent suppliers in case one is late? Why are they cutting it so close with their supply chain? Surely after being in business for over 40 years Bombardier should have supply chain and production management figured out?
My guess is that BBR knows our expectations are pretty low by this point, and that Toronto is numb to further delivery failures. So, they made a Hail Mary promise knowing that if they make it they look like stars, and if they don't, well it looks like business as usual at BBR. No harm either way.