Thanks for the testing!

when I discovered the issue at 12am today eastern time (yes I called...), it is upgrade available to first class by dummy booking. I called, the agent said yes we do have the space available for complimentary upgrade, but her help desk could not solve the problem. Then this morning when I woke up, 3 first class seats were gone and it turned upgrade eligible.

I called customer care, they basically said that is reservation's business. Reservation said you can pay and feels like I'm crazy saying I saw I can select first class for free.

Maybe I should push a little bit more when I called midnight, when I tried to HUCA, the same agent picked up my phone... so no bother.

Just my datapoint, next time when you see this, be more careful...