diff --git a/shiftregister/app/models.py b/shiftregister/app/models.py
index 197cc2e..550d79f 100644
--- a/shiftregister/app/models.py
+++ b/shiftregister/app/models.py
@@ -149,9 +149,9 @@ class ShiftRegistration(models.Model):
 
     def __str__(self):
         return f"{self.helper.name}: {self.shift}"
-    
+
     def is_checked_in(self):
-        return self.state==self.RegState.CHECKED_IN
+        return self.state == self.RegState.CHECKED_IN
 
 
 class Message(models.Model):
diff --git a/shiftregister/signage/views.py b/shiftregister/signage/views.py
index cd8e310..a506c6e 100644
--- a/shiftregister/signage/views.py
+++ b/shiftregister/signage/views.py
@@ -7,6 +7,7 @@ from .models import TeamBackup
 from .models import Shift
 from .forms import TeamBackupForm
 from datetime import timedelta
+from django.db.models import DateTimeField
 
 # Create your views here.
 @login_required
@@ -16,9 +17,15 @@ def worklist(request):
     )
     shifts = (
         Shift.with_reg_count()
+        .annotate(
+            end_at=ExpressionWrapper(
+                F("start_at") + F("duration"),
+                output_field=DateTimeField(),
+            )
+        )
         .filter(
             help_wanted,
-            start_at__gt=timezone.now(),
+            end_at__gte=timezone.now(),
             deleted=False,
         )
         .order_by("start_at", "room_id")
@@ -48,9 +55,15 @@ def terminal(request):
     )
     shifts = (
         Shift.with_reg_count()
+        .annotate(
+            end_at=ExpressionWrapper(
+                F("start_at") + F("duration"),
+                output_field=DateTimeField(),
+            )
+        )
         .filter(
             help_wanted,
-            start_at__gt=timezone.now() - timedelta(minutes=20),
+            end_at__gte=timezone.now(),
             deleted=False,
         )
         .order_by("start_at", "room_id")
diff --git a/shiftregister/team/forms.py b/shiftregister/team/forms.py
index 1f94351..ba7c2ce 100644
--- a/shiftregister/team/forms.py
+++ b/shiftregister/team/forms.py
@@ -10,10 +10,9 @@ class NameField(forms.ModelChoiceField):
     def label_from_instance(self, user):
         return f"{user.name} ({(str(user.phone))[-3:]})"
 
+
 class HelperShift(forms.Form):
-    helper = NameField(
-        label="Helfer*in", queryset=Helper.objects.order_by("name")
-    )
+    helper = NameField(label="Helfer*in", queryset=Helper.objects.order_by("name"))
 
 
 class BulkMessage(forms.Form):
diff --git a/shiftregister/team/urls.py b/shiftregister/team/urls.py
index 884f6e5..a71118e 100644
--- a/shiftregister/team/urls.py
+++ b/shiftregister/team/urls.py
@@ -11,5 +11,5 @@ urlpatterns = [
     path("shift/<int:pk>", views.shift_detail, name="shift"),
     path("helper/<int:pk>", views.HelperDetail.as_view(), name="helper"),
     path("message/", views.bulk_message, name="bulk_message"),
-    path("checkin/<int:pk>", views.checkin, name="checkin" ),
+    path("checkin/<int:pk>", views.checkin, name="checkin"),
 ]
diff --git a/shiftregister/team/views.py b/shiftregister/team/views.py
index a854daa..2b26a13 100644
--- a/shiftregister/team/views.py
+++ b/shiftregister/team/views.py
@@ -141,17 +141,24 @@ class FreeShiftList(ShiftList):
         ) & Q(room__required_helpers__gt=F("reg_count"))
         return (
             Shift.with_reg_count()
+            .annotate(
+                end_at=ExpressionWrapper(
+                    F("start_at") + F("duration"),
+                    output_field=DateTimeField(),
+                )
+            )
             .filter(
                 help_wanted,
-                start_at__gt=timezone.now(),
-                deleted = False,
+                end_at__gte=timezone.now(),
+                deleted=False,
             )
             .order_by("start_at", "room_id")
         )
 
+
 @login_required
 def checkin(request, pk):
     reg = get_object_or_404(ShiftRegistration, pk=pk)
     reg.state = reg.RegState.CHECKED_IN
     reg.save()
-    return redirect("team:shift", pk=reg.shift.pk)
\ No newline at end of file
+    return redirect("team:shift", pk=reg.shift.pk)