I sent this query off to Dish TV support - I know there are other users of this satbox that are experiencing this:

"Lately I have a box pop up while watching TV notifying me that a series/single episode has ended.  Quite a large box and you have to exit the box to get back to the programme you are viewing.  You can even be watching a recorded programme from your library.  Is there a way to turn this off or will you do a firmware fix to take it off.  This issue has been raised by other people in Freeview forum."

I have just had a reply back from support@dishtv.co.nz:

"Yes we have a new firmware release this month and included will be a
change so the box only appears when you go into your library. "