What does this mean, exactly? Are the planes not X or is it the crew is Y? Or, is the ticket/flight sold by X and the plane and crew are Y? What's all this silliness?
BTW, I had a rather displeasure 1.5 years ago on a return flight. I chose to carry my camera onto the plane in a very small carry-on bag (much smaller than what a lot of people try to get away with. This was a Delta flight that I didn't know was being outsourced.
First, my priority boarding wasn't honored by this 3rd party in Delta sheep's clothing and then my small carry-on bag was forcibly checked--something I absolutely detested. I learned after the fact that the flight wasn't operated by Delta. NEVER again will I allow this.
It is like buying a Mercedes CLS AMG and discovering it is a Toyota. Not knocking Toyota, but if I'm paying for a Merc I want a Merc. Same goes for air travel. If I pay for BA, VA, etc., I don't want to be outsourced to Delta. And yes, I am now seeing and filtering flights based on these outsourcing aspects.