Put it all in perspective of who you know. Your group of friends who are instructors, and politically motivated when it comes to 2A issues may have sent notice. But of the 20 - 25 friends of mine not on this board that I know have permits, I guarantee none of them have given notice. So from my perspective, it's probably a pretty small number.
But what it comes down to, as I understand it, we really have no idea how many unique permit holders of those 75,000 have given notice.