Didn't Newsnight do their own breaking news coverage when Nelson Mandela died? Though of course that hapenned just before the programme started not during, and probably could have aired 30 minutes later in Scotland if needed
Tony Currie has posted the story elsewhere of Newsnight being extended at the last minute to take a live speech. Newsnight Scotland has a fixed end time which is meant to be the same time that network Newsnight comes off air but frequently isn't exactly to time.
One this occasion, Newsnight Scotland had finished at the planned time and Tony was running the pre-recorded weather when it was announced on talkback that Newsnight was staying on air. With no way to cleanly crash back to the network programme, he ended up playing a load of trails and doing a menu and some music, because he kept being told that they would be finishing "any minute now"
Write that down in your copybook now.