The film was first retitled A New Hope in the Art of Star Wars first edition. Edited by Carol Titelman.
That was in 1979 i think.
So 1981 was when they actually bothered to do it, to physically alter the opening roll up and starfield and add a new second title to the film. They even spliced the new opening into existing prints.
I’m sure ILM has talked about redoing the opening somewhere.