Some 12 years ago I saw a film Juno, and commented on it: Film Review: Juno and here. As I observed at the time, as well as its humour, the film shows how an unplanned pregnancy can be viewed in a positive way and explores how all those involved - the parents, the boyfriend and school friends - respond to the situation. If I recall correctly, it includes a scene where Juno leaves an abortion clinic, in effect making the decision to continue her pregnancy. Wikipedia gives a fuller account of the film here.
The title role of Juno was played by Ellen Page, who has now "come out as 'trans'". It is sad to see just how quickly sources such as Wikipedia, for example, are willing to change the casting in their post about the film from "Ellen" to "Elliot". Because the role of Juno in the film is not just a female role; because of the nature of the film's plot, it is an essentially feminine role, too.
Whilst there is a courtesy in addressing someone now in the way in which they ask to be addressed, without that implying anything other than courtesy towards the person, it will be unfortunate if a retrospective "re-gendering" should in any way overshadow the essentially female casting of a film that pre-dates transition. Whilst I might greet him now as Elliot, in Juno she remains Ellen Page.