U/H/Q are the lowest eligible economy fares. G&E is premium economy and Y/B/M the most expensive.
For C->F upgrade, J, D, C fares are eligible, Z and P fares are not.

Can't use a GPU to upgrade on Swiss. Also, GPUs on LH are for one segment, so even if your second flight was also LH you'd require another GPU to upgrade.

See the whole thread on this.
http://www.flyertalk.com/forum/unite...tml?styleid=17