diff --git a/docs/changelog.rst b/docs/changelog.rst
index c8a6893..89721cb 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -1,9 +1,6 @@
 Changelog
 =========
 
-* :release:`0.15.1 <2023-07-23>
-* :bug:`-` remove stale disk usage stats older than 30 minutes
-
 * :release:`0.15.0 <2023-07-23>
 * :feature:`10` add disk usage details for mail and web
 
diff --git a/gnuviechadmin/gnuviechadmin/__init__.py b/gnuviechadmin/gnuviechadmin/__init__.py
index b31a146..d1d1bd2 100644
--- a/gnuviechadmin/gnuviechadmin/__init__.py
+++ b/gnuviechadmin/gnuviechadmin/__init__.py
@@ -1,4 +1,4 @@
 # import celery_app to initialize it
 from gnuviechadmin.celery import app as celery_app  # NOQA
 
-__version__ = "0.15.1"
+__version__ = "0.15.0"
diff --git a/gnuviechadmin/hostingpackages/views.py b/gnuviechadmin/hostingpackages/views.py
index 37cd749..ea5b4ac 100644
--- a/gnuviechadmin/hostingpackages/views.py
+++ b/gnuviechadmin/hostingpackages/views.py
@@ -6,7 +6,6 @@ from __future__ import absolute_import
 
 import http
 import logging
-from datetime import timedelta
 
 from django.conf import settings
 from django.contrib import messages
@@ -14,7 +13,6 @@ from django.contrib.auth import get_user_model
 from django.contrib.auth.mixins import PermissionRequiredMixin, UserPassesTestMixin
 from django.http import Http404
 from django.shortcuts import get_object_or_404, redirect
-from django.utils import timezone
 from django.utils.translation import gettext as _
 from django.views.generic import DetailView, ListView
 from django.views.generic.edit import CreateView, FormView
@@ -280,8 +278,8 @@ class AddHostingOption(StaffUserRequiredMixin, FormView):
 class HasDiskUsageUploadPermission(BasePermission):
     def has_permission(self, request, view):
         return (
-                request.user.has_perm("hostingpackages.add_customerpackagediskusage")
-                and request.method == "POST"
+            request.user.has_perm("hostingpackages.add_customerpackagediskusage")
+            and request.method == "POST"
         )
 
 
@@ -294,15 +292,12 @@ class UploadCustomerPackageDiskUsage(APIView):
         if request.content_type != "application/json":
             return Response("Unacceptable", status=http.HTTPStatus.BAD_REQUEST)
 
-        submitted_sources = set()
-
         for row in request.data:
             user = row["user"]
             for key in row:
                 if key == "user":
                     continue
                 else:
-                    submitted_sources.add(key)
                     for item, size in row[key].items():
                         try:
                             package = CustomerHostingPackage.objects.get(
@@ -320,9 +315,7 @@ class UploadCustomerPackageDiskUsage(APIView):
 
                             if key == "mail":
                                 try:
-                                    ma_mb = package.mailboxes.get(
-                                        username=item
-                                    ).mailaddressmailbox_set.first()
+                                    ma_mb = package.mailboxes.get(username=item).mailaddressmailbox_set.first()
                                     if ma_mb:
                                         metric.email_address_id = ma_mb.mailaddress_id
                                 except Mailbox.DoesNotExist:
@@ -334,12 +327,6 @@ class UploadCustomerPackageDiskUsage(APIView):
                                 "hosting package for user %s does not exist", user
                             )
 
-        if submitted_sources:
-            CustomerPackageDiskUsage.objects.filter(
-                source__in=submitted_sources,
-                modified__lt=timezone.now() - timedelta(minutes=30),
-            ).delete()
-
         logger.info("usage data submitted by %s", request.user)
 
         return Response("Accepted", status=http.HTTPStatus.ACCEPTED)
@@ -369,7 +356,7 @@ class CustomerHostingPackageDiskUsageDetails(StaffOrSelfLoginRequiredMixin, Deta
         mail_usage, web_usage, mysql_usage, pgsql_usage = [], [], [], []
 
         for usage in self.get_object().customerpackagediskusage_set.order_by(
-                "-used_kb"
+            "-used_kb"
         ):
             if usage.used_kb <= 0:
                 continue
diff --git a/pyproject.toml b/pyproject.toml
index 2bde72f..48a9242 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "gva"
-version = "0.15.1"
+version = "0.15.0"
 description = "gnuviechadmin web interface"
 authors = ["Jan Dittberner <jan@dittberner.info>"]
 license = "AGPL-3+"