Tomorrow is a big day and I could really use a flat bed tonight to fly across the country. The problem: United's international-config 757s have only 16 seats in BusinessFirst and 153 in economy class, a bad ratio for upgrading a hub-hub transcon route.
Nevertheless, I do stand a chance--
So why blog about this? Merely to point out that I will fly across the country tonight in business class--the question is just whether I will have a lie-flat bed or standard domestic first class seat.
When flying United Airlines, my advice is always to take the sure thing when applying a confirmed upgrade instrument. That means, if there is (R) class on a flight, try to make it work so you don't have to sweat out an upgrade waitlist. Ideally, you confirm an upgrade on your desired flight, but sometimes it just doesn't work that easily. Instead, you confirm on a less-desirable aircraft type or at a less-desirable time.
Then, with United's wonderful confirmed same-day flight change, you can quickly switch flights (without cost for United elites and Star Alliance Gold members) if your original fare class is available on the new flight(s) (and usually any remaining (F) space translates to identical (R) space at around the 23hr40min mark before the flight). You can even add a connection if you want, as long as you stick to a published routing. And if you were using miles/GPU/RPU to upgrade, if there is (R) class on your new flight, agents should immediately confirm the upgrade.
But here's an extra piece of insurance you can attempt to secure: you can keep your confirmed upgrade and waitlist for your earlier desired flight. That's what I am doing tonight. You'll have to find an agent willing to assist, but I've personally had very good luck at most legacy UA hubs or on the phone.
And here's what else I've found--if you are in (R) class on a confirmed instrument (again miles/GPU/RPU), you can waitlist directly into (R) class on the desired flight. I suspect there will be some comments below about how this is against the rules or only an anomaly, but it has happened to me on several occasions--I consider it a quirk of SHARES.
The conventional wisdom is that you must waitlist for economy (for your original booking class), then go onto the upgrade list again if you clear the flight. Again, this may be the rule, but in my experience this is not the way it is done in practice (unlike with legacy United). On more than one instance, I have found myself simultaneously at the top of the flight upgrade waitlist and standby waitlist.
I do not believe this would be the case for complimentary upgrades, which also come out of the (R) fare bucket but are prioritized differently by the system, but this maye be a valuable option for getting the flight you want while not sacrificing your confirmed upgrade at a less ideal time.