Newark airport will no longer be NYC-area airport due to upcoming city code change

Starting Oct. 3, Newark Liberty International Airport will no longer be considered a New York City-area airport due to an upcoming change in their city code.
The reasoning is because of a new standard for "multi-airport cities.” As a result, EWR will stay, but it will lose its New York City code component.
This change to the city status is according to the International Air Transport Association.
According to a Luftansa memo, this could affect costs because Newark will operate under a new pricing structure.
Whether or not it will be cheaper than JFK or LGA is not known yet.
However, airlines could charge a penalty fee for switching flights from EWR to JFK or LGA since it's no longer under that city code.