thanks for all the reply, knowing that it works for you guys prompt me to did one more try. i realized that the expert mode result interface changed recently and by default, it collapse without showing the fare number, while it used to display all the fare availability by default without me clicking on it.
another weird thing is united opened up more business/first seat for sale, when i searched earlier today, there was only 3 seats left (which i confirmed by talking to an agent sunday night), but it shows there are more than 7 seats left at this moment.
i guess the agent did not really look into the availability seat chart either and probably simply pulled out the same data that i saw and provided me the wrong information.
finger crossed and hope the clear the upgrade in the next day or two for this 14 hours flight.
thanks again