This is the confirmation about what I have been expecting for a long time in various other posts. I also tend to think that this service won't remain seasonal, and that they'll be extended throughout the year.
Flight numbers are AA170 and AA169. The aircraft will be arriving in ZRH at 10.15, just in time to catch SR's noon hub (both European and Intercontinental). Departure from ZRH is set at 14.30, i.e. within Swissair's first afternoon longhaul hub, where also the Japan flights are located. I have understood that the aircraft will be a B767-200ER initially.
Regarding extra Swissair operated flights, once again, no news is available so far. Anything is possible for the upcoming summer, but pending some changes in the airline's China service, for which extra aircraft might be needed.