Strange seat map for 777
I'm booked on BA185 to EWR in November, which is a 4-class 777. Unfortunately I am travelling in World Traveller, as I simply couldn't justify Club for a 36hr trip.
Upon checking the seat map to see what was available, I was presented with a map where World Traveller starts in row 21 (for the DEF seats...22 onwards for ABC DEF HJK) and end in row 35.
Every seat map I've found for BA 777's seem to have completely different configs, either starting in rows 26 or 28 for the 4-class or in row 15 for the 3-class.
Any ideas what plane this is? And what kind of equipment can I expect on this route in World Traveller?