The musical "Tikitikitanga" that is performed in the film is loosely based on Emily Bronte's Wuthering Heights.
Emma Kinane (Charlie the stage manager) is married to Michael Nicholas Williams (Stephen the musical director) and their children Barnaby Kinane Williams and Claire Kinane Williams appear as the sound tech and the assistant stage manager.
Upstage was filmed in 9 days.
Jonathan Morgan (who is an accomplished singer) is the only one who doesn't do his own singing. His singing voice is supplied by (female) opera singer Aivale Cole.