So you are departing IAD and LAX on 1/1 and ORD on 1/2? If so your flights are respectively, F9 P9 R9, F4 P3 R0, and F6 P2 R0. You have a decent chance of a CPU on the first flight, and a much lesser chance on two and three. The red-eye out of LAX looks particularly chancy (and I might say just plain unlikely for a Plat). Note that while you could confirm the upgrade right now with an RPU on the first flight, the second and third would waitlist.

I would watch UA208 during the upgrade window. If you don't clear at T-72, and R is dwindling, I would consider applying the RPU prior to T-24. If I wanted to sit up front on the return, I would waitlist that RPU right now and keep my fingers crossed.