46 U.S.C. § 7106

(a) In General .— A license issued under this part is valid for a 5-year period and may be renewed for additional 5-year periods; except that the validity of a license issued to a radio officer is conditioned on the continuous possession by the holder of a first-class or second-class radiotelegraph operator license issued by the Federal Communications Commission. (b) Advance Renewals .— A renewed license issued under this part may be issued up to 8 months in advance but is not effective until the date that the previously issued license expires or until the completion of any active suspension or revocation of that previously issued license, whichever is later.