Thanks for posting - but so many use online services to grab cancellations for hard to get spots that these will likely be gone in seconds after you cancel.
I use
https://wanderinglabs.com. You put in where you want to go and when and even give it specific info about where in the CG you want to go and what features you want and it texts you as soon as that space becomes available.
It works great. I've used it 4 or 5 times and it's never failed to get me the spot I wanted in a filled up campground.
Not to take away from your kind gesture of letting us know, but thought it might helps others in the future.