Thanks Dave - it says YUPP on the Detailed Fare Rules, books to P 1st class, and seat maps to rows 1 to 6 on a 736, so seems to be there - a bit too good to be true!
We're YUPPing the HNL-WAS return component (connection DFW), deep discount economy WAS-NYC, NYC-MIA, MIA-WAS in between, meaning...