Livre d'Or

I was curious! It could have been something else, but I know Ps150 is in the SoP, and it's three movements, so I wondered :)

And I did not know that it's normal for professional singers to sub in for solo roles at the last minute

Yeah, I mean, obviously normally it's all booked months in advance! But there's always short-notice changes happening somewhere, particularly because with singing you don't want to do it if you're even just mildly off-colour or have a scratchy throat or something. I think that stuff like big opera, where they do the same piece every day for weeks, may well be very different - what you were expecting is how I believe it works in theatre, which again does the long runs - but most concert performances you really are only doing one concert, or maybe two, in a project, so it doesn't make sense to build in that specific local redundancy, I think. Everyone's mobile anyway, doing concerts all over the place, and it's all short-term bookings (a couple of days or so) which means there's a kind of pool of available talent just generally?

My information is based on a mix of singing in concerts which have soloists and things I've heard my sister talk about (she's an artist manager mostly in opera, arranging bookings and logistics and so on for a set of client singers), so I think I'm right but I definitely don't know all the subtleties. :)