I cannot remember reading about movies that cast actors so late in the production!
I don't think it's that uncommon. After all, it can take months to shoot a film, so you don't necessarily need to cast a role before shooting if you won't be filming their scenes until later in the process.
There have, of course, been cases when a role was re
cast shortly after shooting began, like Hugh Jackman replacing Dougray Scott as Wolverine and Viggo Mortenson replacing Stuart Townsend as Aragorn.