I am sorry, there is no setting available in the current EasyBlog. You need to modify the code to achieve this. You can find the code here in this file: /components/com_easyblog/themes/vintage/blog.item.php line: 32. May I know which template you're using because the code location is different from each other.
Perhaps you can provide us with backend access and FTP access as well so that we can assist you further on this issue. Also can you please tell us more how do you wish to change the date.