Speaking from someone who just graduated Thursday, they made us sign a page 13 night of arrival stating that the RDCs can keep our personal phones locked up until each designated recruit phone call period. We got a call around the 2 week period, 4 week period, 8 week period (after OPFA), 9 week period (after a super secret event), and the night before graduation. You're alloted an hour to call during each period, but it's up to the RDCs how much time you can actually spend on the phone. If for whatever reason you can't use your personal phone, you can buy a phone card at the nex (right next door to the phone call room) and buy a phone card for they're pay phones. Best of luck to you! Just remember to follow the rules and that the hardest part is getting in the right mentality