Originally Posted by FightingIlliniUAL
The OP was referring to the check-in process, not after checking in.
The Online FAQ's for Easy Check-in Online is not up to date...
"Can I make seat assignment changes with EasyCheck-in Online?
EasyCheck-in Online will automatically assign a seat to you. Once you check in and print your boarding pass, requests for seat assignment changes must be made at the gate."
Easy Check-in FAQ's
The outdated part, now that I re-read it, is that you also have an option to change your seat during the check-in process and there is a new process for making changes after the check-in process. I retract my earlier assessment.