I've tracked CO 89/99 often, and they almost always fly NNE towards Baffin Island in N. Canada, and then join one of the Polar Routes. CO99 to HKG doens't have the option (not enough range) of going west through Hudson Bay and northern Alaska, but perhaps CO89 to PEK does.

But for the vast majority of flights, they will go NNE out of EWR. I believe that's to catch some of the tailwind for the early portion between EWR and the North Pole, rather than going straight north.

CX's JFK-HKG, CA's JFK-PEK and AC's YYZ-HKG & YYZ-PEK all fly the same route. One can check the initial paths on flightaware.com each day.