I am flying on a domestic ticket, IAD-LAX. 757. Inventory is offering NC1/ NF0, so it looks like there is still 1 confirmable upgrade to first. But the agent has told me that only international connections can confirm this, not domestic travelers seeking upgrades.

I am 99% certain that I have gotten advanced confirmed NC upgrades on two cabin planes on domestic itineraries in the past. But I may be having a senior moment as well.

Should I bother calling back, or is this the way it is?