30 Miss. Code. R. 1001-5.1
Except as otherwise provided by Miss. Code Ann. § 33-1-39, all licenses expire after December 31st of odd numbered years and shall be invalid unless renewed. To avoid a late payment fee or lapse of a license, all licenses must be renewed no later than 12:00 p.m. CST on December 31st in each odd-numbered year. Subject to a late payment fee, licenses may be renewed after December 31st until 12:00 p.m. CST on March 31st of the immediately succeeding even-numbered year through the same process as set forth herein.
A renewal made by mail is deemed received upon the post-mark date as marked on the envelope. In the absence of a post-mark date on the envelope, a renewal is deemed received by the Board upon the actual date of receipt. An on-line renewal is deemed received by the Board as of the date of its electronic submission.
30 Miss. Code. R. 1001-5.1