Booking flight for August 2025 in December. Bad idea?

I'm a bit surprised to learn that flights from Regina to Toronto 8 months from now are almost $800. Is December a bad time to book flights? I'm wary of waiting for 2025 because Air Canada is going to start charging for carry-on baggage then. Online, people say it's better to wait 30 to 3 months until the trip to get good deals, but I know this often doesn't work. So I was just wondering if booking in December is a bad idea. Also, I've heard of people booking a flight somewhere in the US and just not taking the second flight. Has anyone here tried that? Thank you