When calling ExportMap with a JSON return format, an HREF field is included with a URL to the image you requested. I'm assuming this is a generated temporary file. I would like to know how long that file exists.
Is its lifespan a duration since it was generated or are those temporary files purged at a specific time of day (like 4am)? If purged at a specific time, if a map was requested 1 minute before the purge, would it be purged 1 minute later?