Long story short I've been working on a return flight ORD-NRT-SIN on my CO miles for a friend of mine to join me. I've managed to get UA First seats on 3 out of the 4 flights however there is only award availability on UA in economy class for the whole round trip ticket on the NRT-SIN leg that is shown to CO. I have some extra UA miles to burn and was able to book a business class ticket on the NRT-SIN leg so she can join me up front as she will be meeting me in Tokyo. Is this going to cause any issues with her having a ticketed seat in economy and another seat in business? What should I tell the agent upon checking her in at NRT?

I don't see how it can work. If she does not check in and board with her NRT-SIN segment on the round-trip, the rest of her itinerary will be canceled. And if she uses her Coach BP to board, her Business Class seat will be canceled when she fails to board.

It's a very interesting question and I've thought about for a similar situation. How would this differ from a musician who buys another seat for their instrument to ride in Y while they sit in F? The problem may be the same name on the reservation. It would depend, I would think, on whether that leg has some form of "secure flight" to deal with.

If you booked the instrument in F and the instrument switched seats with your friend in Y what would be the problem? You'd have to have something "fragile" to buckle into the seat so when they did a seat count their numbers would match.

Also people who buy 2 seats on a plane turn in both boarding passes and just tell the GA it's an extra seat so both are checked in.

You could call with a hypothetical and ask how to book an award seat for an object--whether it be an instrument, some fragile item or box of precious memories you don't want to check or in the shared overhead bin and see what they say.

Let us know how it turns out.

As long as the GA scans your two boarding passes, you should be good to go.

Obtaining boarding passes is easy, no one will question anything if you use Mr. Chicken. There's a chance however that the GA may start asking questions, so if I were you I'd just board with the bulk of the crowd--I woulnd't camp on the red carpet

Someone pointed out that musicians can buy two seats... it's true, anyone can do so in theory, but then both seats are on the same PNR.

There's also anecdotical evidence that United's reservation sytem cancels duplicate reservations, but while I've found this to be true for held itineraries I've never seen it happen with confirmed itineraries. Besides, nothing in the CoC prohibits duplicate bookings.

Bottom line: if I were you I'd try, and hope that the GA doesn't start asking useless questions.

I've done this before- thought not internationally. it was LAX-JFK and I was travelling with a lap child.

UA reservations (still dont understand this but whatever), they couldnt apply a regional to my LAX-JFK route, and I was not high on the waitlist for UDU's. But by buying an award seat in F, I could "bypass" all of that. But I still wanted to earn EQMs for LAX to JFK. The gate agent gave me a really hard time, but I told her (nicely of course) musicians and obese people do this all the time. My coach seat is in the bulkhead. my F seat was the last row of F. She called her supervisor who confirmed what I was doing was totally allowed, and they just made sure to scan both tickets.