F3G why should Y class who have paid to be on that flight have to be bumped just to keep C class happy? What a pompous stance to take, unbelievable!
The dilemma for the airline is very straightforward, they should compensate the C class passengers for having the Cabin downgraded to Y.
At the end of the day C class passengers are important to an airline, are they more important than Y passengers ? In the cold light of day the answer is yes, they are. They tend to be fairly frequent travellers paying a huge premium, they also tend to be the ones making the decisions on where to place their employers money when it comes to travelling.