Odd. There was only one other instance where I've seen them cut out of news and go to something else and it happened a number of decades ago, a story I've related here before. Instead of what was then called CityPulse Tonight at 11 PM, a rerun of "Life on Venus Ave." was shown. No word on what happened. 

I knew someone who worked there so I called him to find out what was going on. They had what police called a "credible bomb threat," and they evacuated the building (299 Queen St. W. at the time) with every employee on duty that night standing outside on Queen St. as the cops searched the premises. (When "Venus" ended, the thing rewound on air and a black screen followed for about 15 minutes. There was no one in Master Control to switch to anything else.)

By the time the cops were through and nothing was found, everyone was allowed back in. But by then, it was long past news time and everyone went home. It's the only other time I can recall something like that happening at City TV. 

They were back on for the 11, so whatever it was, has been fixed.