Changing the subject slightly, what is the take on the change in upgrade priority criteria? Yes, Million Miler is the third tiebreaker, but take a look at item 2 on the new tiebreaker list effective January 1, 2024. It says that "Cabin Purchased (Original + Paid Upgrades)" is the second tiebreaker. It used to say "Fare Class Groupings."

Does this mean that if you bought Comfort+, you would be ahead of everyone who bought Main Cabin?

Scroll down on the linked page: Upgrades