Typically renting has no bearing on refusing mail delivered. It's your current domicile. If they are coming into your property to deliver the mail, you could post no trespassing and call the cops on them.
Courts spend time on all manner of things, so in fact they would spend 8 minutes on it.
Not sure what the Canadian trespass laws are but would that work?
In the UK you’d have to ask a trespasser to leave first as it’s a civil matter.
If they don’t leave immediately or they threaten you then it’s criminal and you can call the cops.
So if you don’t catch them trespassing you can’t really do anything about it later.
Does Canada treat trespass a crime?
Here, if damage is done during trespass that’s also different. Which is why I think I’d go the small claims court route for the cost of clean up and time spent dealing with it.
Courts spend time on all manner of things, so in fact they would spend 8 minutes on it.