Please go to WP Masonry > Layouts. From there please click on Copy To WordPress theme for default theme. Then you will get the new location of the layout theme. Please go to that location and open the layout.php file.
In Line no. 13 which looks like this.
<a href="<?php comments_link(); ?>"><?php comments_number('0 Response', '1 Response', '% Responses' ); ?></a>
Change it to
<?php the_time('F j, Y'); ?>
This should meet your requirement.