I did BOLC before dental school so I was pretty squared away but if that doesn't apply to you then definitely meet with your recruiter so you know how to wear the uniform, salute, etc.
Some schools that require externships can have the ADT replace that requirement so look into that. To be an official ADT (meaning orders, funding) it needs to be 21-45 days in length - shorter than that you can still get permission to visit but finding/transportation/housing will be up to you.
Technically you are not credentialed and will hold no privileges so you cannot do any procedures - it's not like working under someone else's license at school. Some programs will relax that rule but make absolutely sure that you establish clear boundaries with your sponsor and don't overstep, it can get you and a lot of other people in trouble. If your sponsor says you will only be shadowing then absolutely do not touch a patient regardless of what any provider/assistant tells you is "okay".
Roxanne will set everything up for you but get in touch with her early and often, like everything in the military it takes longer and is more complicated than it should be. She will cut you individual orders that will explain travel (flights over certain distance authorized through Carlson Wagonlit travel agency) and rental car (unlikely but depends on the post). You will most likely stay in an IHG Army hotel.
This will be like a working job interview for you, it's an excellent opportunity to impress some of the people that have a stake in your application and hopefully get a letter of recommendation. Make sure you are prepared, read up on what you'll be seeing beforehand, and be the first person there and the last to leave.
