They will NOT rebook you on another airline in case of a delay. I had a family who flew a couple of weeks ago from TLV to EWR via BCN. The flight from TLV was delayed an hour (in advance of the flight). They would not rebook them in TLV on another airline (even though it was quite clear that they'll miss their connection), and when they did miss the connection, they just rebooked them on the exact same Norwegian flight the following day leaving them in BCN for over 24 hrs.
I believe Aeroflot is somewhat better, though they don't linger far behind....