diff --git a/aircox/tests/models/test_schedule.py b/aircox/tests/models/test_schedule.py
index 6d1a662..7730915 100644
--- a/aircox/tests/models/test_schedule.py
+++ b/aircox/tests/models/test_schedule.py
@@ -56,8 +56,8 @@ class TestSchedule:
         assert schedule.dates_of_month(at) == []
 
     @pytest.mark.django_db
-    @pytest.mark.parametrize("months", range(0, 25, 2))
-    @pytest.mark.parametrize("hour", range(0, 24, 3))
+    @pytest.mark.parametrize("months", range(0, 25, 4))
+    @pytest.mark.parametrize("hour", range(0, 24, 4))
     def test_dates_of_month_last(self, months, hour):
         schedule = baker.prepare(
             Schedule, time=time(hour, 00), frequency=Schedule.Frequency.last
@@ -81,8 +81,8 @@ class TestSchedule:
     # since the same method is used for first, second, etc. frequencies
     # we assume testing every is sufficient
     @pytest.mark.django_db
-    @pytest.mark.parametrize("months", range(0, 25, 2))
-    @pytest.mark.parametrize("hour", range(0, 24, 3))
+    @pytest.mark.parametrize("months", range(0, 25, 4))
+    @pytest.mark.parametrize("hour", range(0, 24, 4))
     def test_dates_of_month_every(self, months, hour):
         schedule = baker.prepare(
             Schedule, time=time(hour, 00), frequency=Schedule.Frequency.every
@@ -97,8 +97,8 @@ class TestSchedule:
             last = dt
 
     @pytest.mark.django_db
-    @pytest.mark.parametrize("months", range(0, 25, 2))
-    @pytest.mark.parametrize("hour", range(0, 24, 3))
+    @pytest.mark.parametrize("months", range(0, 25, 4))
+    @pytest.mark.parametrize("hour", range(0, 24, 4))
     def test_dates_of_month_one_on_two(self, months, hour):
         schedule = baker.prepare(
             Schedule,