In both cases, an in-house investigation would be the most productive. Are they not scanning all boxes before they're put on the trucks to distributors? Are they monitoring the rest of their inventory properly? Especially since they've had these issues before, that seems like the area they need to be focusing on.
But as has been said, getting stuff before street date is extremely common. I suspect a large portion of this community has gotten stuff early. We've had people post about getting D&D books from stores before the street date and no one came out of the woodwork to scold them for doing so.
It is bizarre that suddenly so many people seem to have a problem with this, when I suspect we can see many of the same people in those old threads, asking about whether a given subclass was updated since the UA or what levels one of the adventures in the book is for.