Your statement that the judge concluded that their line maintenance would in fact be sufficient is not actually true. The judge said, and I quote:
In summary I find that Air Canada does maintain operational and overhaul centres in those cities by maintaining overhaul operations under its contracts with Aveos and by itself maintaining certain overhaul functions through its line maintenance operations.
It said “and”, not “or.” It did not say “either/or”. It did not say it could drop one, and therefore be in compliance. It must do both.
I wonder if someone can explain to me how you've now come to the conclusion that the judge did not say “by maintaining...contracts with Aveos”.