"I just checked and Joslyn was well into her 30s by the time she understudied Johanna in the original production, don't expect this same casting for the film."
Well, yes, casting someone in their thirties as Johanna would be ridiculous when Depp isn't that far into his forties, but someone in their twenties being cast in the role doesn't seem all that unlikely.
"The gods who nurse this universe think little of mortals' cares. They sit in crowds on exclusive clouds and laugh at our love affairs. I might have had a real romance if they'd given me a chance. I loved him, but he didn't love me. I wanted him, but he didn't want me. Then the gods had a spree and indulged in another whim. Now he loves me, but I don't love him." - Cole Porter