Originally Posted by corporate-wage-slave

This has happened a few times already, usually there is enough notice (4 or 6 months) so that everyone can be accommodated. Occasionally there are reports of people being dragged down to CW, but YouFirst has a good reputation for finding alternative options. One example was when some Newark services went from 14 seat First to 787-9, which is 8 seats, where it's an easy solution: offer a JFK replacement. Nothing is guaranteed in aviation, but still it's unlikely to be a problem, either you are booking so far out that changes can be handled, or your flight equipment is pretty much settled. You do have the option of cancelling and getting a full refund, but I doubt it will come to that.