New Braunfels actually, not sure if you're allowed to camp at GC, but I'll check. What about a BCGB overnighter?
You're not supposed to camp at BCGB or City Park or anywhere else I've camped. Doesn't mean you can't. Ride til you get tired, walk off the trail a few feet and set up camp. Simple as that. I've camped at City Park a couple times now and have been probably 10 feet off trail and well concealed and got to listen/watch as people road by. Pretty fun stuff. You're right, this weather is finally starting to come around where it would be nice to camp.