Amasty Product Feed for Magento 2 / Google feed / Date format

Google asks date in a specified format:

"Date range (use ISO 8601 standard). Submit a start date and an end date with time and timezone of format YYYY-MM-DDThh:mm[±hhmm] or YYYY-MM-DDThh:mmZ, separated by slash ( / ) (for example,2016-02-24T13:00-0800/2016-02-29T15:30-0800)"

How can I setup the correct date format that Google asks?