Fly by Night and Day
3 Decades of Experience working for United Airlines!
Go to united.com and pull up your reservation. You can change seats in your ticketed class but in order to use miles you need to make a new reservation. You can ask for a seat change also at the gate before departure.
Global resources for your trip. Currently Position- United Club; Main customer contact at the airport...
additional information below
How to purchase Economy Plus on the integrated United website