Currently the process to renew a firearms license is identical to the process for obtaining a new license. The only difference between a new license and a renewal is that if you already have a license and you are within 90 days of expiring to no more than 30 after expiring, you can request a temporary renewal license that is valid for 90 days when you apply. That way you can continue carrying while the appliction is being processed.
Temporary Renewal License
Any person who holds a license under this Code section to carry a pistol or revolver may, at the time he applies for a renewal of the license, also apply for a temporary renewal license if less than 90 days remain before expiration of the license he then holds or if his previous license has expired within the last 30 days.
Unless the judge of the probate court knows or is made aware of any fact which would make the applicant ineligible for a five-year renewal license, the judge shall at the time of application issue a temporary renewal license to the applicant.
Such a temporary renewal license shall be in the form of a paper receipt indicating the date on which the court received the renewal application and shall show the name, address, sex, age, and race of the applicant and that the temporary renewal license expires 90 days from the date of issue.
During its period of validity the temporary renewal permit, if carried on or about the holder's person together with the holder's previous license, shall be valid in the same manner and for the same purposes as a five-year license.
A $1.00 fee shall be charged by the probate court for issuance of a temporary renewal license.
For those that have less than 2 months before your license expires, it would probably be a good idea to get a temporary renewal when you apply.