BoringBoredBoard40 said: "The age difference between Amy and Tyne is quiet a gap so that is interesting"
As discussed in other posts about this revival, I don't think the age really matters for the characters are long as she is "of a certain age."
John Patrick Shanley has approved casting of a 48-year-old (Cherry Jones), a 59-year-old (Meryl), a 72-year-old (Eileen Atkins), a 60-year-old (Dearbhla Molloy in London), a 77-year-old (Tyne), and now a 55-year-old (Amy). She's in a wimple (bonnet?) the whole time; it's not hard for a skilled actor to play a little older if that's the take on the role.
For Father Flynn, Shanley has approved casting of him being 38 (Brian O'Byrne), 41 (Ron Eldard & Philip Seymour Hoffman), 30 (Padraic Delaney in London), and now 56 (Liev). That character being a contemporary of Sister A could provoke interesting dynamics, too.
I was meant to see the show tonight via Hiptix, but I called Roundabout and they honored an exchange for a future date with no questions asked. I was very pleased with their customer service!