All flight segments must fall within the same-day confirmation policy.
You will need to ask to be put on the standby list for each individual flight.
You may lose your seat if:
You're not on your domestic flight 15 minutes before it departs.
You're not on your international flight 20 minutes before it departs.
If you’ve asked to be on the standby list but don’t see your name, check with a United agent at the airport. This issue can only be resolved at the airport.
To change a trip, select the individual traveler during the first step in the change process. Then, you can continue to change flights for just that traveler.
To cancel a trip, you must divide the reservation. That will create multiple individual reservations, and then you cancel the applicable reservation. To divide the reservation, select the individual cancel option in the travelers section on the reservation.