diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 2a1868f..92e83ea 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -2,7 +2,6 @@ name: Tests
 
 on:
   push:
-  pull_request:
 
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
@@ -31,7 +30,7 @@ jobs:
       matrix:
         python: ${{ fromJSON(needs.generate-matrix.outputs.python-versions) }}
         rf-version: ${{ fromJSON(needs.generate-matrix.outputs.rf-versions) }}
-    name: Windows (${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
+    name: Windows (python-${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
     steps:
       - name: Checkout the repository
         uses: actions/checkout@v4
@@ -51,7 +50,7 @@ jobs:
       matrix:
         python: ${{ fromJSON(needs.generate-matrix.outputs.python-versions) }}
         rf-version: ${{ fromJSON(needs.generate-matrix.outputs.rf-versions) }}
-    name: Linux (${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
+    name: Linux (python-${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
     steps:
       - name: Checkout the repository
         uses: actions/checkout@v4
@@ -70,7 +69,7 @@ jobs:
       matrix:
         python: ${{ fromJSON(needs.generate-matrix.outputs.python-versions) }}
         rf-version: ${{ fromJSON(needs.generate-matrix.outputs.rf-versions) }}
-    name: MacOS (${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
+    name: MacOS (python-${{ matrix.python }}, robotframework-${{ matrix.rf-version }})
     steps:
       - name: Checkout the repository
         uses: actions/checkout@v4
diff --git a/src/oxygen/oxygen.py b/src/oxygen/oxygen.py
index 825c146..dce6f85 100644
--- a/src/oxygen/oxygen.py
+++ b/src/oxygen/oxygen.py
@@ -99,7 +99,6 @@ def output_file(self, path):
         result.visit(OxygenVisitor(self.run_time_data))
         result.save()
 
-
 class OxygenLibrary(OxygenCore):
     '''Oxygen is a tool to consolidate different test tools' reports together
     as a single Robot Framework log and report. ``oxygen.OxygenLibrary``
diff --git a/src/oxygen/robot3_interface.py b/src/oxygen/robot3_interface.py
index 22b0385..e1a72f5 100644
--- a/src/oxygen/robot3_interface.py
+++ b/src/oxygen/robot3_interface.py
@@ -288,6 +288,9 @@ def ms_to_timestamp(self, milliseconds):
         tz_delta = self.get_timezone_delta()
 
         time_object = datetime.fromtimestamp(int(milliseconds / 1000)) - tz_delta
+        if time_object.year < 1970:
+            time_object = datetime.fromtimestamp(0)
+        # fromtimestamp() loses milliseconds, add them back
         milliseconds_delta = timedelta(milliseconds=(milliseconds % 1000))
         time_object = (time_object + milliseconds_delta)
 
diff --git a/src/oxygen/robot4_interface.py b/src/oxygen/robot4_interface.py
index d1b0cce..e4f4779 100644
--- a/src/oxygen/robot4_interface.py
+++ b/src/oxygen/robot4_interface.py
@@ -5,8 +5,6 @@
                                 TestCase as RobotResultTest,
                                 TestSuite as RobotResultSuite)
 
-from robot.model import BodyItem
-
 from robot.running.model import TestSuite as RobotRunningSuite
 
 
@@ -227,6 +225,8 @@ def spawn_robot_keyword(self,
         start_timestamp = self.ms_to_timestamp(start_time)
         end_timestamp = self.ms_to_timestamp(end_time)
 
+        # import this here so RF4 interface stays in parity with RF3
+        from robot.model import BodyItem
         if setup:
             keyword_type = BodyItem.SETUP
         elif teardown:
@@ -284,11 +284,13 @@ def timestamp_to_ms(self, timestamp):
 
         return milliseconds
 
-
     def ms_to_timestamp(self, milliseconds):
         tz_delta = self.get_timezone_delta()
 
         time_object = datetime.fromtimestamp(int(milliseconds / 1000)) - tz_delta
+        if time_object.year < 1970:
+            time_object = datetime.fromtimestamp(0)
+        # fromtimestamp() loses milliseconds, add them back
         milliseconds_delta = timedelta(milliseconds=(milliseconds % 1000))
         time_object = (time_object + milliseconds_delta)
 
diff --git a/tests/utest/robot_interface/test_time_conversions.py b/tests/utest/robot_interface/test_time_conversions.py
index 2d96e3d..4a4498b 100644
--- a/tests/utest/robot_interface/test_time_conversions.py
+++ b/tests/utest/robot_interface/test_time_conversions.py
@@ -9,25 +9,42 @@ def setUp(self):
 
     def test_should_be_correct(self):
         timestamp = self.interface.result.ms_to_timestamp(1533625284100.0)
-        assert timestamp == '20180807 07:01:24.100000'
+        self.assertEqual(timestamp, '20180807 07:01:24.100000')
 
         timestamp = self.interface.result.ms_to_timestamp(1533625284451.0)
-        assert timestamp == '20180807 07:01:24.451000'
+        self.assertEqual(timestamp, '20180807 07:01:24.451000')
 
     def test_should_be_associative(self):
         timestamp = '20180807 07:01:24.300000'
 
         milliseconds = self.interface.result.timestamp_to_ms(timestamp)
-        assert milliseconds == 1533625284300.0
+        self.assertEqual(milliseconds, 1533625284300.0)
 
         timestamp = self.interface.result.ms_to_timestamp(milliseconds)
-        assert timestamp == '20180807 07:01:24.300000'
+        self.assertEqual(timestamp, '20180807 07:01:24.300000')
 
         milliseconds = self.interface.result.timestamp_to_ms(timestamp)
-        assert milliseconds == 1533625284300.0
+        self.assertEqual(milliseconds, 1533625284300.0)
 
         timestamp = self.interface.result.ms_to_timestamp(milliseconds)
-        assert timestamp == '20180807 07:01:24.300000'
+        self.assertEqual(timestamp, '20180807 07:01:24.300000')
+
+    def _validate_timestamp(self, result):
+        timestamp = result.ms_to_timestamp(-10)
+        expected = '19700101 00:00:00.990000'
+        import platform
+        # Particular Windows 10 calculates epoch differently ( T ʖ̯ T)
+        if platform.system() == 'Windows' and platform.version() == '10.0.19044':
+            expected = '19700101 02:00:00.990000'
+
+        self.assertEqual(timestamp, expected)
+
+    def test_ms_before_epoch_are_reset_to_epoch(self):
+        from oxygen.robot4_interface import RobotResultInterface as RF4ResultIface
+        self._validate_timestamp(RF4ResultIface())
+
+        from oxygen.robot3_interface import RobotResultInterface as RF3ResultIface
+        self._validate_timestamp(RF3ResultIface())
 
 
 class TestTimestampToMs(TestCase):
@@ -36,19 +53,19 @@ def setUp(self):
 
     def test_should_be_correct(self):
         milliseconds = self.iface.result.timestamp_to_ms('20180807 07:01:24.000')
-        assert milliseconds == 1533625284000.0
+        self.assertEqual(milliseconds, 1533625284000.0)
 
         milliseconds = self.iface.result.timestamp_to_ms('20180807 07:01:24.555')
-        assert milliseconds == 1533625284555.0
+        self.assertEqual(milliseconds, 1533625284555.0)
 
     def test_should_be_associative(self):
         milliseconds = 1533625284300.0
 
         timestamp = self.iface.result.ms_to_timestamp(milliseconds)
-        assert timestamp == '20180807 07:01:24.300000'
+        self.assertEqual(timestamp, '20180807 07:01:24.300000')
 
         milliseconds = self.iface.result.timestamp_to_ms(timestamp)
-        assert milliseconds == 1533625284300.0
+        self.assertEqual(milliseconds, 1533625284300.0)
 
         timestamp = self.iface.result.ms_to_timestamp(milliseconds)
-        assert timestamp == '20180807 07:01:24.300000'
+        self.assertEqual(timestamp, '20180807 07:01:24.300000')