Originally Posted by
Q Shoe Guy
Aren't you a 1K...they should open the door for their best customers.....and then you can use UA's shower products......
To answer the question, even if you sit in an F seat, your boarding pass will say C if the flight is operated as 2-cabin service. If you check the seatmap for the flight, it should already have the F cabin open for allocation.
There is contradictory evidence in the other thread about whether F->C is allowed F lounge at NRT - some say yes, others say no.