This value represents the date and time when eBay processed the request. This value is returned in GMT, the ISO 8601 date and time format (YYYY- MM- DDTHH:MM:SS.SSSZ). See the "dateTime" type for information about the time format, and for details on converting to and from the GMT time zone.
Version number for the current search metadata (product or compatibility). If you are maintaining search metadata locally, compare this value to the version of the search metadata you last downloaded to determine whether the data may have changed.