https://www.flyertalk.com/forum/29641532-post545.html
UA is putting only 24 PE seats on the 787-10, 772, and 77W. The real estate for PE is coming directly out of E+ on these planes, not that E+ is so hot on any of them (and down right awful on the 10 across 777) but what UA has done is basically split the space it currently gives for E+ into PE and E+