It's not fully my area of expertise. If they were operating spectrum, they would have to get spectrum licences from the industry department. If they were starting as a new carrier, they would have to abide by various CRTC regulations—providing alerting, providing 911, and so on. Otherwise, they would be treated as any other entrant, provided they had less than 10% market share.
On February 8th, 2022. See this statement in context.