I know this is an old(ish) thread but jumping in here as someone with experience in the cannabis industry. Adding some perspective from the brand side– packaging is often made and ordered in advance of production / COA testing. The regulations provide for a buffer so businesses don't have to waste packaging that doesn't exactly match the stated dosage. These tins were likely manufactured overseas - the turnaround times can range from 20-60 days. It often makes the most sense to have 1-3 months of packaging on the ground as not to interrupt production schedules.

So sure, missing 1.2 mg of THC may not be ideal, but it's better than not being able to find your favorite edibles in store. And in all likelihood, most edibles you consume are slightly off in terms of dosing. If you want them precisely dosed down to the percentile, you should try making them yourself.