From the Tricare Prime Remote website:
Family Member CoverageFamily members must reside with the sponsors to enroll. If you have family members who live in a separate location from the TRICARE Prime Remote-enrolled sponsors, they may enroll in TRICARE Prime if its offered where they live or they can be covered by TRICARE Standard and Extra.
What I can't find from the website is what happens if a MM lives in a military area and the family member doesn't. It sounds as though Prime Remote might not be a possibility and that you will have to enroll in Standard. But I am no expert.
Your friend needs to call a Tricare Service Center (not the appointment line) ask the very specific question of "I am in a remote location and my sponsor is on a military base. Can I enroll in Tricare Prime Remote in this case?"
Kate ~ 7/3/09 *** Connor ~ 11/11/10
4 miscarriages: 2007, 2009, 2013, 2014
No more TTC for us. We are done, and at peace, as a family of 4.
"Suffering has been stronger than all other teaching, and has taught me to understand what your heart used to be. I have been bent and broken, but – I hope – into a better shape.” — Charles Dickens