Originally Posted by
EWR764
As a business market, LHR does not drive as much premium leisure demand as Southern Europe in the summer, and business demand dips a bit too. Simultaneously, there is greater demand for Y. While the 76L is a great platform for EWR-LHR most of the year, I think United has found that it does not have enough Y capacity in the market for the summer, hence the upgauge now that it has some more 787s available.
While I am hopeful for the 78P and think EWR-LHR will get it eventually, I'm not sure how the aircraft rotation would work out for this flight, so it is probably premature.
I think that UA would be well-suited to un-densify and turn the 788 fleet into the successor to the high-J 763s on EWR-LHR once those head out to pasture (scrap).