What does LR do if the Preview folder fills up? I know the acr cache deletes the oldest files when it fills up, but does LR do the same with the preview folder?
I don't think it can fill up.
Do you mean if the hard disk that the previews are on fills up? I would imagine this would cause the program to give you an error message and stop running if it can't write to a location.
Retrieving data ...