Follow My Blog Post - default selected the "Notify followers for this update" option to page or post

wpw_fp_post_update_email_notify_field.php

<?php

function wpw_fp_default_update_email_notify_field($notify_field) {

	$notify_field['default'] = true;
	
	return $notify_field;
}

// add filter to default check notify followers email checkbox
add_filter( 'wpw_fp_post_update_email_notify_field', 'wpw_fp_default_update_email_notify_field', 10, 1 );