The spot on the Jewel trail is way, way, way down off the ridge and as Peakbagger said, it's a toilet pit. It's seems a lot farther then 0.6 miles. And being the only spot and being well known, what are the chance of finding space there late in the day? Slim.
Crag Camp and Gray Knob are currently closed. I have not heard if there are plans to open them later this summer. The Perch is open, but has very limited space and fills up early, it can't be counted on. Hammocks are useless unless you drop down into the hardwoods, which start at about 3,000 feet and even then it's iffy due to the dense underbrush.
Starting up the Valley Way at 10 AM is okay if your going to stay at the Madison Spring hut. You MIGHT make it to the Perch before dark but getting there so late is a problem. Getting all the way to the Jewel trail? Not likely.
Like I said, hike up to the Valley Way tent site and get a nice, early start at dawn the next day or maybe shoot for sunrise on Madison.
This is from last February, looking at the ridge the Jewel trail follows down from the Gulf Side trail. The blue line is about where that small flat area is located.
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Looking back towards Adams and Madison from the Gulf Side near the top of the Jewel trail.
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