Originally Posted by
TTmex
and looked up BA source as well and I'm not seeing a row 20 on the 787-800. Am I missing something

Look
very VERY closely on the BA source, where I have put the red box - there is at tiny "20" and also notice the small line just below it that joins 21ABC to the
second row in the middle three.

And from BA.com you can see the same: