The "published" (non-e-fare) int'l fares -- those most popular to/from Europe -- now include language that prevent use of any upgrades, including systemwides.

? please explain: what kind of 'published int'l fares to/from Europe will now/in-the-near-future be excluded from upgrades with systemwide-1K-vouchers?

I had no problem to get confirmed upgrades (using systemwide 1K-vouchers) for future transatlantic flights with deep discounted fares on UA (just yesterday).