Cities can have special override rates for their state and/or county. Counties can have special override rates for their state.
As of Build 72 override details get the following values from the Rate & Boundary Database overriding record rather than from the record being overridden:
Authority
Effective Date
Location Code
As of Build 73 override details get the following values from the Rate & Boundary Database overriding record rather than from the record being overridden: