Every employee holding a position in the classified or unclassified service, who has left or shall leave the position by reason of entering the armed forces of the United States (whether through membership in the reserve of the United States Military or Naval Forces or in the Rhode Island National Guard or Naval Reserves, when any of the foregoing units are called to active federal or state duty, or by reason of enlistment, induction commission or otherwise), and who has held a position in the classified or unclassified service for one hundred eighty (180) or more calendar days within the twelve (12) months next preceding entrance into the armed services, and who at the time of entrance into the armed services had family medical benefits, shall continue to be eligible to receive family medical benefits, in the same manner as available prior to entering service, for designated family members, excluding the employee, during the duration of his or her absences required by the continuance of service in the armed services and his or her return to classified or unclassified service. Nothing in this section, however, shall require the employee to continue family medical benefits provided by the state of Rhode Island or prevent the employee from enrolling in or receiving medical benefits from another source of health insurance coverage including the federal medical benefits program for deployed members of the armed services.