It took 17 days to hear back that everythings been approved. (Recently went through.)
To reiterate some advice:
If you are Guard/Reserve rent a car or coordinate with others. WP is a huge base which is subdivided. It's about a 10 minute drive from billiting to the exam site. Also, having a car will allow you the freedom to get out. Definitley checkout the US Air Force Museum, the Presidential/Experimental Museum, and the Wright Brothers Airfield (Huffman Prairie). For good eats/drinks there's a snazzy outdoor mall type thing...on Greene Blvd.
If you can, get there a day early to see the above and get orientated with the area. (The front desk will give you an outdated map to the testing site and if left till the last moment you'll be driving cirlces getting all antsy in the pantsy.) Your FC-1 will be administered in the USAFSAM Building 20840 Area B. If you're not given any other instruction I would show up at the test site on day one of your exams at 0700. Bring DVD's to watch with the rest of the folks because there will be a bit of waiting around.
Once there try not to stress yourself out. As far as the FC-1 goes...it is what it is. Some guys struggled getting the zzzzz's because of anxiety. Things you can do in advacne are: get down to weight, take care of cavitiies, etc. If you are worried about something see you eye doc or family practice doc to put your mind at ease.
As stated before, everyone at Wright Pratt is very helpful and want you to succeed. If you are having issues they will do their absolute best to help get you squared away.