I was just in the store and asked about this. He said that everything is on the cloud now, so if you don't change accounts or locations, you don't lose your saved programs by just changing the Box.
It depends on the age of your x1 box. If you have a newer one, no because there is a cloud backup. If not, then yes.
If it's the main box you will. But if it's just one the extion boxes (bedroom etc.) then you won't.
Thanks! Your answer is awaiting moderation.