[rp272]

I added a book today by an author whose book is already in Calibre and the Author Sort field displays all in caps (unlike the previous book). If I type in the sort field as I expect it to be then it has a red border suggesting it is wrong.
I cannot find how Calibre applies the conversion and I do not understand why it has just started to happen.
Please can anyone help

P.S. I've just looked at the first book that was OK but this now shows the Author Sort in caps.
The Author's name is Stephen Williams which converts to WILLIAMS, STEPHEN
This doesn't appear to happen with other Authors