Doesn't appear to loosen up restriction on retirees or visitors.
... I am a retiree and a qualified (credentialed) retired DOD LEO.
If this is any help, DODI 5525.12 Implementation of the Amended Law Enforcement Officers Safety Act of 2004 (LEOSA), Feb 13, 2014 updated Aug 1, 2016.
Dumb question - Can you ask for permission to keep a firearm locked in your car while on base? When I was working I was able to get permission to have a locked firearm in my car while at work. Also, can you ask for permission to carry concealed while on base? I'm not sure how the military works now. I was in the Coast Guard fifty years ago.