A channel (and CTV before) don't usually air previews anymore it seems. So if I don't see them, I don't see them. I don't go out of my way to see them. I do consider them spoilery as well.
I rated this ep Above Average. But I'd rather rate it Very Good. It was unfortunately a lot of stuff we could have guessed already. It was interesting that his mom knew that she was sending him back to get killed by her in the past. And very sad