As of August 17, 2015:
Per the recent passage of Georgia Senate Bill 100, if a vehicle fails its annual emissions inspection, and the motorist has already paid all related taxes and fees, they may contact their local county tag office for information about a possible non-renewable 30-day extension on the registration.
Motorists with failing inspections are still required to seek repairs to pass their retest, in order to complete registration. The possible extension is intended to assist motorists that are still seeking repairs while driving with expired tags.
Motorists with questions should contact their county tag office. CGAF does not administer these extensions and cannot assist motorists in this area.
Source: https://www.cleanairforce.com/wp-content/uploads/2015/08/GM_30-Day-Extension_VIR-Notice.pdf