tallarch
I may be wrong, but think the Ca
$h and miles Upgrade that UA offers ($550 and 20K miles each way) is your best way into the front cabin. European carriers tend to value the front cabin more.
If you were to fly 100K miles in a year you would get 6 System Wide Upgrades (GPU) that can be applied to W or higher classes of fare and partake in what we at UA forum call the "W Lottery," because the required R class is rarely available at time of booking

(I say that as a Plat, who will accidentally reach 1K in December).
Lots of folks deserting UA, but for my mostly TATL flying still find them the best value.
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