Maybe the terms for theatrical structure differ between the countries?

That does sort of remind me of the movie adaptation of The Madness of George III being titled “The Madness of King George,” so as not to confuse US audiences who, to be fair, are less likely to see the name George and automatically think “Ah, yes, one of England’s kings,” and might therefore suppose The Madness of George III was the third installment of a “Madness of George” movie series.