This also shows 1 unused permit for last Sunday; and yet a friend of mine last Saturday was declined a permit for a Sunday dayhike.
If he was there after the 2 PM time when the permits are all passed out and they told him that, then I would call the Visitor Center and ask about it. I would sure be interested to know what they say.
...maybe somebody actually got their permit, then decided not to hike, and came back in and turned it in.
Edit: I see the FS changed their number to zero for that date, so I changed it above, as well.
