Bell was the first to Launch Cat-M1 a few months ago (LTE bands 4, 5, 17): https://business.bell.ca/shop/iot-bell-partner-program
Rogers launched a month ago (not sure which bands): Rogers to launch national LTE-M network to power the next era of IoT in Canada - About Rogers
TELUS launched a few weeks ago (LTE Bands 2, 4, 12): www.telus .com/en/on/business/internet-of-things/low-power-wide-area
I’m fairly certain that there’s no real plans for NB in the next 6-12 months for Canadian carriers. They are notoriously cheap and have no financial incentive to do a massive infrastructure upgrade of narrowband equipment.