I'll give the most radical iteration. It can be walked back easily.

Ben survives the DS duel, is rescued by Luke, but is too injured to participate in the battle of Yavin. He coaches Luke through it with the Force. In ESB, he is still recovering and on a mission for the rebel leadership on the opposite side of the galaxy from Hoth. He tells Luke through the Force to find Yoda. Yoda gives some expo about Force ghosts. Ben contacts Luke through the Force to tell him that he couldn't reach cloud city before Luke.

I'm not sayin' I ever intended to get that rad, just trying to make things consistent with past impressions and what seemed like past GL iterations.