I have no doubt that April is in the movie and now I am pretty sure that BC is playing ... Yes ... An deaged April ... Cause I could have find the way how he deaged himself! And what is needed?! Yes Carol Marcus! As she is developing Genesis and we learned that Prime Spock was reborn more or less through it in ST3, BC/April uses Genisis for deage him and help his ill member of family! And in the end Carol Marcus saves the Day as Chris Pine told us in an former interview! Weller is maybe as mentioned before Admiral Marcus as he is the One which operates against his daughter and helps April in some way maybe! It was also mentioned with the New Vulcan colony would be Part of the movie so I feel thats not the strangest theory!