There is a bill introduced to get rid of ALL requirements to carry in a holster; however, the current law allows carry in ANY type of holster as follows:
LINK:
16-11-126.html
(c) This Code section shall not permit, outside of his or her home, motor vehicle, or place of business, the concealed carrying of a pistol, revolver, or concealable firearm by any person unless that person has on his or her person a valid license issued under Code Section 16-11-129 and the pistol, revolver, or firearm may only be carried in a shoulder holster, waist belt holster, any other holster, hipgrip,
or any other similar device, in which event the weapon may be concealed by the personīs clothing, or a handbag, purse, attache case, briefcase, or other closed container. Carrying on the person in a concealed manner other than as provided in this subsection shall not be permitted and shall be a violation of this Code section.
I think this qualifies for ankle carry.