Given the nature of technology and the way we access our information, it doesn't really work in terms of geographic location, so it would have to be a blank advertisement. None of the three jurisdictions I cited—Nova Scotia, Manitoba, and Saskatchewan—have experienced adverse effects, so I don't know what the impact would be nationally. Again, we do it every election for a longer period of time, so a by-election seems to me a lower threshold.
On September 28th, 2017. See this statement in context.