diff --git a/src/bdew_datetimes/calendar.py b/src/bdew_datetimes/calendar.py
index e0229d2..e4b5fcb 100644
--- a/src/bdew_datetimes/calendar.py
+++ b/src/bdew_datetimes/calendar.py
@@ -7,7 +7,7 @@
 from typing import Any
 
 from holidays import HolidayBase, HolidaySum
-from holidays.constants import APR, DEC  # type:ignore[attr-defined]
+from holidays.constants import DEC, JUN  # type:ignore[attr-defined]
 from holidays.countries.germany import Germany
 
 
@@ -29,8 +29,9 @@ def _populate(self, year: int) -> None:
         self[date(year, DEC, 24)] = "Heiligabend"
         self[date(year, DEC, 31)] = "Silvester"
         if year == 2025:
-            self[date(2025, APR, 4)] = (
-                "Sonderfeiertag"  # Anlässlich der Einführung des 24h Lieferantenwechsels
+            self[date(2025, JUN, 6)] = (
+                "Sonderfeiertag"
+                # Anlässlich der (verschobenen) Einführung des 24h Lieferantenwechsels
             )
 
 
diff --git a/tests/test_calendar.py b/tests/test_calendar.py
index 4f55d1c..be2a544 100644
--- a/tests/test_calendar.py
+++ b/tests/test_calendar.py
@@ -30,7 +30,7 @@ def test_bdew_holidays(expected_holiday: date) -> None:
         pytest.param(date(2024, 8, 15), True, id="Mariä Himmelfahrt (BY, SL)"),
         pytest.param(date(2024, 11, 20), True, id="Buß- und Bettag (SN)"),
         pytest.param(date(2024, 12, 31), True, id="Silvester 2024 (BDEW)"),
-        pytest.param(date(2025, 4, 4), True, id="Sonderfeiertag 2025 (BDEW)"),
+        pytest.param(date(2025, 6, 6), True, id="Sonderfeiertag 2025 (BDEW)"),
     ],
 )
 def test_create_bdew_calendar(