Hi fellow FT's

Still pretty much a newbie to this site and don't know all of the nuances and secrets of travelling although I'm a well seasoned traveler so I'm going to have to ask for some advice.

I need to travel from Canada (YYZ or YYC) to (CGN) on April 21. I'm SE and am bringing along a non-status coworker. Which route will give us the best chances of an upgrade (using SWU's only) for the international portion of the journey?

Regards,
YEG_Flyer