Laws regarding firearms are strict. Ran into a couple at Takhini Hot Springs just north of Whitehorse in 2016. They had entered Canada along the southern boarder, spent time in Alaska and were attempting to reenter the Yukon at the Top of the World Hwy crossing heading towards Dawson City. They had chosen to bring a 12 gauge shotgun with them, had followed the Canadian application and fee process and had the necessary paperwork to transport the weapon with them. HOWEVER the female boarder guard and a trainee claimed the law had changed while they were in Alaska and they were declined entry. They had to drive back to Tok, AK, visit a sporting goods store and get a suitable shipping box for a long gun and pay to ship it home to a friend to hold for them till they returned home. They were not happy campers. They had to drive south back to Whitehorse and then north and approach Dawson City from the south.
The last I knew of regarding this :
Once the firearms permit is issued, it is valid for 60 days and required to reapply if it exceeds that timeframe...
If there is any change of enforcement that super cedes the current 60 day issue, I would tend to think they would not have a valid 60 day permit to transport the shotgun, but rather an approval for less than 60 days until the new enforcement date is to take effect and they were well aware of that valid timeframe...
If the 60 day valid permit was in fact issued and the permit was still valid upon re-entering within the 60 days, I would have requested a supervisor to make that kind of judgement call and politely ask why I was not informed of a new law in effect when I was issued a current 60 day permit that is still valid...
Upon a quick research, I do not see any immediate changes posted to regulations regarding transport of importing firearms into Canada, the reg is the same with no changes as far as I am reading.
Now I am curious of what this "new law" is that I cannot currently find, or based on what was mentioned with the couple's story posted that was told by them on the real reason they were denied entry reference to the firearm....I will try to find out more regarding this and keep that in mind for future reference.
Regardless, Customs officials do have the discretion of denying entry for many reasons right or wrong, and that would kinda hurt having to turn back 123 miles to Tok and endure that kind of inconvenience if this was exactly the case.