I doubt you’ll see either again on the Medium term. Something like an A321LR would be better if they wanted these types of routes to work. Even EDI seat use was often pretty low on A35/78. If A380s and some 777s are being withdrawn then the domino effect means 787s needed on other routes.
But we’re often told that cargo on widebodies is what keeps these afloat (although that can easily be transferred elsewhere by road)