The tip date and conclude time of your celebration in ISO-8601 structure. Use the exact same format as startDate. Incorporate both the date and time so users can discover occasions that suit into their agenda. For online occasions, you have to specify the timezone by including the UTC or GMT https://addons.prestashop.com/en/seo-natural-search-engine-optimization/31857-automatic-google-rich-snippets-json-ld-open-graph-seo.html