Seems to be another problem as my flight is now one week and 21 hours away.
That means that even in the very unlikely event that they are changing menu exactly the same day as my flight , they now only have a few hours left to meet their deadline to publish new menu one week before the change...
About your question re the upgraded pax, I´d say they´ll have no inferior treatment.
Plats should be offered to choose food first. Sometimes that works, sometimes not.
But after that they just take the orders from the front to the back without any considerations if passengers are op-uped, voucher/point upgraded or fully paying.