A covered servicemember means a member of the Armed Forces, including a member of the National Guard or Reserves, and/or a veteran of the Armed Forces, including a veteran of the National Guard or Reserves, who is undergoing medical treatment, recuperation, or therapy, is otherwise in outpatient status, or is on the temporary retired list, for a serious injury or illness. Such veteran is considered a covered servicemember if he/she was a member of the Armed Forces, including the National Guard and Reserves, at any time during the five-year period preceding the date on which the veteran undergoes medical treatment, recuperation or therapy. A covered servicemember of the Armed Forces would have a serious injury or illness if he/she has incurred an injury or illness in the line of duty while on active duty in the Armed Forces or if he/she has an injury or illness that was incurred before the covered servicemember's active duty and was aggravated by service in the line of duty while on activity duty; provided that the injury or illness may render the servicemember medically unfit to perform duties of the member's office, grade, rank or rating. A serious injury or illness of a veteran is further defined to encompass an injury or illness incurred in the line of duty while on active duty, or which existed prior to active duty but was aggravated by service in the line of duty while on active duty, and that manifested itself either before or after the covered servicemember became a veteran.