In November on a Sunday my wife and I will arrive at TBIT at 6:30 am on the SQ flight from ICN on an SQ F award ticket. There are UA award seats available in Y at 8 am, that I believe we can add on to the itinerary. We'd just have carry-on bags and we both have Global Entry. Am I correct in assuming:

1. That we have a good shot of making the 90 minute TBIT-T7 connection, which would be completely airside.
2. That since this would be one ticket, if we added on that 8 am UA LAX-SFO leg United should accommodate us if we miss the connection.
3. My UA Premier Platinum status would be useless in getting E+ seats, since we'd be on an SQ ticket.
4. There's only a small chance, if any, of UA J seats opening up for that flight.

FWIW, the later LAX- SFO flights that day aren't available as award flights,

If there are any factors I'm not taking into account here, I'd welcome the additional advice/info.

Thanks for any help