diff --git a/mod/assign/classes/event/assessable_submitted.php b/mod/assign/classes/event/assessable_submitted.php
index 362490ba22292..09f8fe45325cd 100644
--- a/mod/assign/classes/event/assessable_submitted.php
+++ b/mod/assign/classes/event/assessable_submitted.php
@@ -41,14 +41,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class assessable_submitted extends base {
-    /** @var \stdClass */
-    protected $submission;
-    /**
-     * Flag for prevention of direct create() call.
-     * @var bool
-     */
-    protected static $preventcreatecall = true;
-
     /**
      * Create instance of event.
      *
@@ -67,31 +59,13 @@ public static function create_from_submission(\assign $assign, \stdClass $submis
                 'submission_editable' => $editable,
             ),
         );
-        self::$preventcreatecall = false;
         /** @var assessable_submitted $event */
         $event = self::create($data);
-        self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->submission = $submission;
+        $event->add_record_snapshot('assign_submission', $submission);
         return $event;
     }
 
-    /**
-     * Get submission instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @since Moodle 2.7
-     *
-     * @return \stdClass
-     */
-    public function get_submission() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_submission() is intended for event observers only');
-        }
-        return $this->submission;
-    }
-
     /**
      * Returns description of what happened.
      *
@@ -152,7 +126,8 @@ protected function init() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        $this->set_legacy_logdata('submit for grading', $this->assign->format_submission_for_log($this->submission));
+        $submission = $this->get_record_snapshot('assign_submission', $this->objectid);
+        $this->set_legacy_logdata('submit for grading', $this->assign->format_submission_for_log($submission));
         return parent::get_legacy_logdata();
     }
 
@@ -163,10 +138,6 @@ protected function get_legacy_logdata() {
      * @return void
      */
     protected function validate_data() {
-        if (self::$preventcreatecall) {
-            throw new \coding_exception('cannot call assessable_submitted::create() directly, use assessable_submitted::create_from_submission() instead.');
-        }
-
         parent::validate_data();
 
         if (!isset($this->other['submission_editable'])) {
diff --git a/mod/assign/classes/event/feedback_updated.php b/mod/assign/classes/event/feedback_updated.php
index 9b9c5ec6cbcf3..2bab6fe3d525a 100644
--- a/mod/assign/classes/event/feedback_updated.php
+++ b/mod/assign/classes/event/feedback_updated.php
@@ -41,6 +41,28 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class feedback_updated extends base {
+    /**
+     * Create instance of event.
+     *
+     * @param \assign $assign
+     * @param \stdClass $grade
+     * @return feedback_updated
+     */
+    public static function create_from_grade(\assign $assign, \stdClass $grade) {
+        $data = array(
+            'objectid' => $grade->id,
+            'relateduserid' => $grade->userid,
+            'context' => $assign->get_context(),
+            'other' => array(
+                'assignid' => $assign->get_instance()->id,
+            ),
+        );
+        /** @var feedback_updated $event */
+        $event = self::create($data);
+        $event->set_assign($assign);
+        $event->add_record_snapshot('assign_grades', $grade);
+        return $event;
+    }
 
     /**
      * Init method.
diff --git a/mod/assign/classes/event/feedback_viewed.php b/mod/assign/classes/event/feedback_viewed.php
index 9166c9d54aa95..18fdec31b2c47 100644
--- a/mod/assign/classes/event/feedback_viewed.php
+++ b/mod/assign/classes/event/feedback_viewed.php
@@ -41,14 +41,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class feedback_viewed extends base {
-    /** @var \stdClass */
-    protected $grade;
-    /**
-     * Flag for prevention of direct create() call.
-     * @var bool
-     */
-    protected static $preventcreatecall = true;
-
     /**
      * Create instance of event.
      *
@@ -65,29 +57,13 @@ public static function create_from_grade(\assign $assign, \stdClass $grade) {
                 'assignid' => $assign->get_instance()->id,
             ),
         );
-        self::$preventcreatecall = false;
         /** @var feedback_viewed $event */
         $event = self::create($data);
-        self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->grade = $grade;
+        $event->add_record_snapshot('assign_grades', $grade);
         return $event;
     }
 
-    /**
-     * Get grade instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @return \stdClass
-     */
-    public function get_grade() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_grade() is intended for event observers only');
-        }
-        return $this->grade;
-    }
-
     /**
      * Init method.
      */
@@ -122,7 +98,7 @@ public function get_description() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        $logmessage = get_string('viewfeedbackforuser', 'assign', $this->grade->userid);
+        $logmessage = get_string('viewfeedbackforuser', 'assign', $this->relateduserid);
         $this->set_legacy_logdata('view feedback', $logmessage);
         return parent::get_legacy_logdata();
     }
@@ -133,10 +109,6 @@ protected function get_legacy_logdata() {
      * @throws \coding_exception
      */
     protected function validate_data() {
-        if (self::$preventcreatecall) {
-            throw new \coding_exception('cannot call feedback_viewed::create() directly, use feedback_viewed::create_from_grade() instead.');
-        }
-
         parent::validate_data();
 
         if (!isset($this->relateduserid)) {
diff --git a/mod/assign/classes/event/statement_accepted.php b/mod/assign/classes/event/statement_accepted.php
index f18ee0a71707a..f9b452f08bec5 100644
--- a/mod/assign/classes/event/statement_accepted.php
+++ b/mod/assign/classes/event/statement_accepted.php
@@ -35,8 +35,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class statement_accepted extends base {
-    /** @var \stdClass */
-    protected $submission;
     /**
      * Flag for prevention of direct create() call.
      * @var bool
@@ -62,26 +60,10 @@ public static function create_from_submission(\assign $assign, \stdClass $submis
         $event = self::create($data);
         self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->submission = $submission;
+        $event->add_record_snapshot('assign_submission', $submission);
         return $event;
     }
 
-    /**
-     * Get submission instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @since Moodle 2.7
-     *
-     * @return \stdClass
-     */
-    public function get_submission() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_submission() is intended for event observers only');
-        }
-        return $this->submission;
-    }
-
     /**
      * Returns description of what happened.
      *
diff --git a/mod/assign/classes/event/submission_duplicated.php b/mod/assign/classes/event/submission_duplicated.php
index 0ed8cb59ac8e0..894ac486fb69b 100644
--- a/mod/assign/classes/event/submission_duplicated.php
+++ b/mod/assign/classes/event/submission_duplicated.php
@@ -35,8 +35,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class submission_duplicated extends base {
-    /** @var \stdClass */
-    protected $submission;
     /**
      * Flag for prevention of direct create() call.
      * @var bool
@@ -62,26 +60,10 @@ public static function create_from_submission(\assign $assign, \stdClass $submis
         $event = self::create($data);
         self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->submission = $submission;
+        $event->add_record_snapshot('assign_submission', $submission);
         return $event;
     }
 
-    /**
-     * Get submission instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @since Moodle 2.7
-     *
-     * @return \stdClass
-     */
-    public function get_submission() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_submission() is intended for event observers only');
-        }
-        return $this->submission;
-    }
-
     /**
      * Returns description of what happened.
      *
@@ -117,7 +99,8 @@ protected function init() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        $this->set_legacy_logdata('submissioncopied', $this->assign->format_submission_for_log($this->submission));
+        $submission = $this->get_record_snapshot('assign_submission', $this->objectid);
+        $this->set_legacy_logdata('submissioncopied', $this->assign->format_submission_for_log($submission));
         return parent::get_legacy_logdata();
     }
 
diff --git a/mod/assign/classes/event/submission_graded.php b/mod/assign/classes/event/submission_graded.php
index d30bdc9917c5f..5f04c83342d5f 100644
--- a/mod/assign/classes/event/submission_graded.php
+++ b/mod/assign/classes/event/submission_graded.php
@@ -35,8 +35,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class submission_graded extends base {
-    /** @var \stdClass */
-    protected $grade;
     /**
      * Flag for prevention of direct create() call.
      * @var bool
@@ -63,26 +61,10 @@ public static function create_from_grade(\assign $assign, \stdClass $grade) {
         $event = self::create($data);
         self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->grade = $grade;
+        $event->add_record_snapshot('assign_grades', $grade);
         return $event;
     }
 
-    /**
-     * Get grade instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @since Moodle 2.7
-     *
-     * @return \stdClass
-     */
-    public function get_grade() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_grade() is intended for event observers only');
-        }
-        return $this->grade;
-    }
-
     /**
      * Returns description of what happened.
      *
@@ -118,7 +100,8 @@ protected function init() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        $this->set_legacy_logdata('grade submission', $this->assign->format_grade_for_log($this->grade));
+        $grade = $this->get_record_snapshot('assign_grades', $this->objectid);
+        $this->set_legacy_logdata('grade submission', $this->assign->format_grade_for_log($grade));
         return parent::get_legacy_logdata();
     }
 
diff --git a/mod/assign/classes/event/submission_status_updated.php b/mod/assign/classes/event/submission_status_updated.php
index 2f27a298493dd..4d1b2078b3842 100644
--- a/mod/assign/classes/event/submission_status_updated.php
+++ b/mod/assign/classes/event/submission_status_updated.php
@@ -41,14 +41,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class submission_status_updated extends base {
-    /** @var \stdClass */
-    protected $submission;
-    /**
-     * Flag for prevention of direct create() call.
-     * @var bool
-     */
-    protected static $preventcreatecall = true;
-
     /**
      * Create instance of event.
      *
@@ -67,31 +59,13 @@ public static function create_from_submission(\assign $assign, \stdClass $submis
                 'newstatus' => $submission->status
             )
         );
-        self::$preventcreatecall = false;
         /** @var submission_status_updated $event */
         $event = self::create($data);
-        self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->submission = $submission;
+        $event->add_record_snapshot('assign_submission', $submission);
         return $event;
     }
 
-    /**
-     * Get submission instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @since Moodle 2.7
-     *
-     * @return \stdClass
-     */
-    public function get_submission() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_submission() is intended for event observers only');
-        }
-        return $this->submission;
-    }
-
     /**
      * Returns description of what happened.
      *
@@ -127,9 +101,8 @@ protected function init() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        global $DB;
-
-        $user = $DB->get_record('user', array('id' => $this->submission->userid), '*', MUST_EXIST);
+        $submission = $this->get_record_snapshot('assign_submission', $this->objectid);
+        $user = $this->get_record_snapshot('user', $submission->userid);
         $logmessage = get_string('reverttodraftforstudent', 'assign', array('id' => $user->id, 'fullname' => fullname($user)));
         $this->set_legacy_logdata('revert submission to draft', $logmessage);
         return parent::get_legacy_logdata();
@@ -141,10 +114,6 @@ protected function get_legacy_logdata() {
      * @throws \coding_exception
      */
     protected function validate_data() {
-        if (self::$preventcreatecall) {
-            throw new \coding_exception('cannot call submission_status_updated::create() directly, use submission_status_updated::create_from_submission() instead.');
-        }
-
         parent::validate_data();
 
         if (!isset($this->other['newstatus'])) {
diff --git a/mod/assign/classes/event/submission_viewed.php b/mod/assign/classes/event/submission_viewed.php
index 31cb225060181..b19723085e35e 100644
--- a/mod/assign/classes/event/submission_viewed.php
+++ b/mod/assign/classes/event/submission_viewed.php
@@ -41,14 +41,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class submission_viewed extends base {
-    /** @var \stdClass */
-    protected $submission;
-    /**
-     * Flag for prevention of direct create() call.
-     * @var bool
-     */
-    protected static $preventcreatecall = true;
-
     /**
      * Create instance of event.
      *
@@ -65,29 +57,13 @@ public static function create_from_submission(\assign $assign, \stdClass $submis
                 'assignid' => $assign->get_instance()->id,
             ),
         );
-        self::$preventcreatecall = false;
         /** @var submission_viewed $event */
         $event = self::create($data);
-        self::$preventcreatecall = true;
         $event->set_assign($assign);
-        $event->submission = $submission;
+        $event->add_record_snapshot('assign_submission', $submission);
         return $event;
     }
 
-    /**
-     * Get submission instance.
-     *
-     * NOTE: to be used from observers only.
-     *
-     * @return \stdClass
-     */
-    public function get_submission() {
-        if ($this->is_restored()) {
-            throw new \coding_exception('get_submission() is intended for event observers only');
-        }
-        return $this->submission;
-    }
-
     /**
      * Init method.
      */
@@ -122,7 +98,7 @@ public function get_description() {
      * @return array
      */
     protected function get_legacy_logdata() {
-        $logmessage = get_string('viewsubmissionforuser', 'assign', $this->submission->userid);
+        $logmessage = get_string('viewsubmissionforuser', 'assign', $this->relateduserid);
         $this->set_legacy_logdata('view submission', $logmessage);
         return parent::get_legacy_logdata();
     }
@@ -133,10 +109,6 @@ protected function get_legacy_logdata() {
      * @throws \coding_exception
      */
     protected function validate_data() {
-        if (self::$preventcreatecall) {
-            throw new \coding_exception('cannot call submission_viewed::create() directly, use submission_viewed::create_from_submission() instead.');
-        }
-
         parent::validate_data();
 
         if (!isset($this->relateduserid)) {
diff --git a/mod/assign/feedback/offline/locallib.php b/mod/assign/feedback/offline/locallib.php
index a16448bd5441c..8845e3cc26496 100644
--- a/mod/assign/feedback/offline/locallib.php
+++ b/mod/assign/feedback/offline/locallib.php
@@ -194,13 +194,7 @@ public function process_import_grades($draftid, $importid, $ignoremodified) {
                                                         'text'=>$newvalue));
 
                             // Trigger event for updating the feedback.
-                            $event = \mod_assign\event\feedback_updated::create(array(
-                                'relateduserid' => $user->id,
-                                'context' => $this->assignment->get_context(),
-                                'other' => array(
-                                    'assignid' => $this->assignment->get_instance()->id
-                                )
-                            ));
+                            $event = \mod_assign\event\feedback_updated::create_from_grade($this->assignment, $grade);
                             $event->set_legacy_logdata('save grading feedback', $logdesc);
                             $event->trigger();
                         }
diff --git a/mod/assign/locallib.php b/mod/assign/locallib.php
index d2af9fe7e57fb..75239c0acb51e 100644
--- a/mod/assign/locallib.php
+++ b/mod/assign/locallib.php
@@ -2012,8 +2012,7 @@ public function get_group_submission($userid, $groupid, $create, $attemptnumber=
 
             $submission->status = ASSIGN_SUBMISSION_STATUS_DRAFT;
             $sid = $DB->insert_record('assign_submission', $submission);
-            $submission->id = $sid;
-            return $submission;
+            return $DB->get_record('assign_submission', array('id' => $sid));
         }
         return false;
     }
@@ -2616,8 +2615,7 @@ public function get_user_submission($userid, $create, $attemptnumber=-1) {
                 $submission->attemptnumber = 0;
             }
             $sid = $DB->insert_record('assign_submission', $submission);
-            $submission->id = $sid;
-            return $submission;
+            return $DB->get_record('assign_submission', array('id' => $sid));
         }
         return false;
     }
@@ -5284,6 +5282,8 @@ protected function process_save_grading_options() {
      * The size limit for the log file is 255 characters, so be careful not
      * to include too much information.
      *
+     * @deprecated since 2.7
+     *
      * @param stdClass $grade
      * @return string
      */
diff --git a/mod/assign/submission/file/locallib.php b/mod/assign/submission/file/locallib.php
index eda470d816bef..981d5ea753d38 100644
--- a/mod/assign/submission/file/locallib.php
+++ b/mod/assign/submission/file/locallib.php
@@ -260,6 +260,7 @@ public function save(stdClass $submission, stdClass $data) {
             $params['objectid'] = $filesubmission->id;
 
             $event = \assignsubmission_file\event\submission_updated::create($params);
+            $event->set_assign($this->assignment);
             $event->trigger();
             return $updatestatus;
         } else {
@@ -272,6 +273,7 @@ public function save(stdClass $submission, stdClass $data) {
             $params['objectid'] = $filesubmission->id;
 
             $event = \assignsubmission_file\event\submission_created::create($params);
+            $event->set_assign($this->assignment);
             $event->trigger();
             return $filesubmission->id > 0;
         }
diff --git a/mod/assign/submission/onlinetext/locallib.php b/mod/assign/submission/onlinetext/locallib.php
index 4e66f58353ccc..c234954602e87 100644
--- a/mod/assign/submission/onlinetext/locallib.php
+++ b/mod/assign/submission/onlinetext/locallib.php
@@ -192,6 +192,7 @@ public function save(stdClass $submission, stdClass $data) {
             $params['objectid'] = $onlinetextsubmission->id;
             $updatestatus = $DB->update_record('assignsubmission_onlinetext', $onlinetextsubmission);
             $event = \assignsubmission_onlinetext\event\submission_updated::create($params);
+            $event->set_assign($this->assignment);
             $event->trigger();
             return $updatestatus;
         } else {
@@ -205,6 +206,7 @@ public function save(stdClass $submission, stdClass $data) {
             $onlinetextsubmission->id = $DB->insert_record('assignsubmission_onlinetext', $onlinetextsubmission);
             $params['objectid'] = $onlinetextsubmission->id;
             $event = \assignsubmission_onlinetext\event\submission_created::create($params);
+            $event->set_assign($this->assignment);
             $event->trigger();
             return $onlinetextsubmission->id > 0;
         }