You can use the filter tkt_sei_metabox_location in order to customize the “Location” where the metabox of TukuToi Send Email If Plugin will appear. This filter determines both where the meteabox appears, and thus, also where the plugin will trigger notifications.

Any valid post type can be passed to this filter, so to enable the plugin feature on the desired post types.
In other words, with this filter you can decide on what Post Types you will want the TukuToi Send Email If Plugin functionality active.

You just need to return an array of valid Post Types in the callback function like in this example:

add_filter('tkt_sei_metabox_location', 'my_custom_metabox_location');
function my_custom_metabox_location(){
  $posts = array('post', 'page');//Array of post Types where the functionality shoud be active. 
  return $posts;