Fixup: use resolved submission start/due dates; use UTC for submission start/due in template

openassessment/templates/openassessmentblock/edit/oa_edit.html

 {% load i18n %}
+{% load tz %}
 {% spaceless %}
 <div id="openassessment-editor" class="editor-with-buttons editor-with-tabs">
     <div class="openassessment_editor_content_and_tabs">
@@ -39,7 +40,7 @@
                             type="text"
                             class="input setting-input"
                             id="openassessment_submission_start_date"
-                            value="{{ submission_start|date:"y-m-d" }}"
+                            value="{{ submission_start|utc|date:"y-m-d" }}"
                         >
                     </div>
                     <div class="wrapper-comp-setting">
@@ -52,7 +53,7 @@
                             type="text"
                             class="input setting-input"
                             id="openassessment_submission_start_time"
-                            value="{{ submission_start|date:"H:i" }}"
+                            value="{{ submission_start|utc|date:"H:i" }}"
                         >
                     </div>
                     <p class="setting-help">{% trans "The date at which submissions will first be accepted." %}</p>
@@ -68,7 +69,7 @@
                             type="text"
                             class="input setting-input"
                             id="openassessment_submission_due_date"
-                            value="{{ submission_due|date:"y-m-d" }}"
+                            value="{{ submission_due|utc|date:"y-m-d" }}"
                         >
                     </div>
                     <div class="wrapper-comp-setting">
@@ -81,7 +82,7 @@
                             type="text"
                             class="input setting-input"
                             id="openassessment_submission_due_time"
-                            value="{{ submission_due|date:"H:i" }}"
+                            value="{{ submission_due|utc|date:"H:i" }}"
                         >
                     </div>
                     <p class="setting-help">{% trans "The date at which submissions will stop being accepted." %}</p>

openassessment/xblock/studio_mixin.py

@@ -93,9 +93,6 @@ class StudioMixin(object):
             except:
                 logger.exception("An error occurred while serializing the XBlock")
 
-        submission_due = parse_date(self.submission_due).replace(tzinfo=pytz.utc) if self.submission_due else ''
-        submission_start = parse_date(self.submission_start).replace(tzinfo=pytz.utc) if self.submission_start else ''
-
         # Every rubric requires one criterion. If there is no criteria
         # configured for the XBlock, return one empty default criterion, with
         # an empty default option.