Thanks for that. A couple of hours is OK, but Mine doesn't seem to run in background. It takes over the whole screen from the start. I've not tried to do anything while its running. I do see the list of several windows containing files. Presumably Time Machine goes through those saving everything, like in duplicate. How would I do an internet search, for example? Or check my emails or write an email,, like I am doing now?
These may seem trivial questions and I can understand anyone doing this regularly would think so.