Comment by schube

Not to mention, there exist airports that are jointly administered by multiple country. One example I know of is EuroAirport Basel Mulhouse, located a few kilometers away from the meeting point of the French, German and Swiss borders. It is located on French soil but administered by both France and Switzerland and has three airport codes: MLH for France, BSL for Switzerland and EAP as a neutral code. The national codes could be used as proxies for timezones if France or Switzerland ever changed their timezone, but what EAP stands for would be challenging to define.