Thanks for the data point. I didn’t think to check to see if I was still confirmed on my original flight until after the plane was in the air. That makes more sense; I was just surprised that it cleared in advance without being called to the podium, as that’s my usual experience. And, I agree it does make sense to hold the confirmed reservation until the standby passenger has boarded.

So, to answer the OP, I guess it should be safe to add yourself to the standby list in advance.

Same Day Flight Change on a SIA Ticket
 

I have a domestic business award ticket from SFO-EWR (I class) booked via Singapore Airlines. Does anybody know if United will allow me to do a SDFC to an earlier flight with this ticket (standby or confirmed)? I know its not a 016 ticket, however in my experience United is pretty liberal in allowing SDFCs outside the officially published constraints if there are seats. I am a Premier Platinum if that makes any difference. Sharing any experiences with a similar situation would be much appreciated!

This is against the posted rules but some agents may be willing

HOWEVER, this needs to be the absolute last segment on the itin if you can find an agent willing or very dire consequences will occur. SQ will not be notified of the SDC but will also not get a notification you took the original flight, leading to a cancellation of all reaming unflown segments.
Standby is no problem.

AC award on UA metal allows same-day standby in UA app. Does anybody know if it also work on TK issued awards?

Anyone know which FF# I should use to get higher standby priority?

My United MP number, with Silver status, or my AC*G status?

If I had to guess, it's that UA treats its home elites better than foreign *G

The answer is yes

Flying SFO-YVR-HND on 016 stock. I'm a little worried about the connection time in YVR, so would like to change to an earlier flight (there are UA and AC options). Existing flight is UA marketed with a UA flight number, but AC operated. Will I be able to SDC to an earlier AC or UA flight if there's space in F, or is this not allowed because it's an AC metal flight?

Earlier AC-operated flight, no. Earlier UA-operated flight, maybe. Until last year, the answer would have been no because YVR-HND is an AC flight. Now, you might have somewhat more luck, but the fact that you're trying to change the operating carrier could pose a problem. The examples I saw last year were all UA metal connecting to OAL metal.

I have an United 016 award ticket EWR - LHR - BOM - CCU. EWR-LHR is on UA and the rest on AI. Am I allowed to do SDC to EWR-DEL nonstop on UA, connecting to DEL-CCU on AI? Thanks

SDC, as we know it? No. However, there are no fees for award changes, so if you find award availability from EWR to CCU via DEL, you should be able to do a regular change for no fee. Any difference in miles will be charged, however.

Thanks. I will stick to the original routing then. The other option is twice the amount of miles.

Either SDC or a regular change would require inventory in your current fare bucket (X/XN for economy, I/IN for business, I'm guessing) to process anyway. When I say you'd have to pay any difference in miles -- UA has been adding between ~2500 and ~4000 miles to prices for close-in bookings. So if inventory opens in your fare bucket, you'll be able to change to it, whether today, the day of travel, or anytime in between -- but you may need to pay this relatively small number of additional miles for the privilege.

If it were an all-UA operated itinerary, SDC would likely be an option, but would still depend upon fare class inventory. The DEL-CCU segment is the problem here.

Got it. I am booked in XN and the EWR-DEL is YN and probably won't go down to XN in time. I have also al alternative LX option for the whole itinerary which I might switch to. It will only be 4,000 extra miles as you point out.

Hello all, quick question on confirmed flight changes / "same day" changes. Say I have a flight departing Sunday at 5pm. If I want to change to a flight the day before, Saturday, at 10pm (less than 24-hrs earlier), would that be covered as a "free" change"? The premier benefits says 24-hrs but the footnote says "same day" and I am not sure which is correct in practice.

Is it best to do this at the airport?

Yes, you would be able to change to the 10 PM Saturday flight for no charge, assuming availability in your fare class, starting 24 hours before your Sunday flight (so, 5 PM Saturday in this case). No need to go to the airport; you can do it on the app or the website, or by calling.