The film is set in 1977, however extras are seen wearing modern (2001/2) clothes and modern cars are seen in the background.
A poster of AC/DC's "If You want Blood, You've got It" is seen hanging on a wall of the production company. The record was released in 1978 (one year after Maria Callas' death).
The view from Callas' apartment window is wrong. It's on avenue Georges-Mandel west of the Eiffel tower so the Invalides which is east of the tower can't be in front of it.