When the JFK services go 3 x daily on the 777, there will be no more -400 Pax service. The reason for the switch was aircraft utilization. CX did not like that the aircraft was sitting overnight in JFK. With only one aircraft type, the time spent on ground is cut down dramatically (not sure how much though).
All the -400 Pax guys out of YVR are being retrained onto the 777 with the exception that a couple are going to the Bus.
MACH.88