Well, just some updated info as we're getting to my departure date!

Seating choice continued to be locked out since I posted last. I am a little concerned that I'm not allowed to change the ANA mileage number to be my UA *G number in the ANA reservation system. I hope that at check in, this works and unlocks any seat privileges.

But I received the bid-my-price email, and was mulling whether to put in a bid from economy to premium economy (the offered range was from 20,000Y to 60,000Y), and at the same time looking at the seat map to get a feel for whether there might be any luck/likelihood of scoring an empty row if not upgrading to premium economy.

The seat map showed the middle section of economy (A380) nearly empty, and premium economy with ~50 seats empty. (I know seat map is not necessarily indicator of actual bookings). So I was on the fence about whether to try for the bid or not.

However, on returning to the email 2 days later, the option was gone. Somehow the bidding has closed early. I would be interested to know how they decide that, or why....

Well, I guess it will be a mystery until check-in window opens, and roll the dice.