Availability from JFK through GVA or ZRH, but not direct to either
Looking at some dates in December, there's availability JFK-GVA-ZRH, or JFK-ZRH-GVA, but not to either city direct... and not to any onward destination (ie JFK-ZRH-IST).
Same results in UA, NH, and Aeroplan search engines, and expert flyer shows no availability at all.
What gives?