FAA1.B Time Frames : 09 Untimely Reason Codes - Overview : C Untimely Reason Codes - Good Cause (UC)
C Untimely Reason Codes - Good Cause (UC)
Key the UC Untimely Reason Code when the determination is untimely, but good cause applies due to an unusual circumstance.
 
This includes, but is not limited to, office closure due to an environmental condition, such as weather, power outage, or unsafe condition.