No, queries are done based on the value in that database. A date time field is stored in standard sql date/time format "Y-m-d H:i:s" If you have everything in your query correct then the something is interfering with the query. I would start here and figure out if the correct query is being run https://ben.lobaugh.net/blog/45390/wordpress-how-to-view-the-sql-query-generated-by-wp_query
