diff --git a/addons/resource/models/resource.py b/addons/resource/models/resource.py
index cb0270b7bfa..a29c8bdd2a5 100644
--- a/addons/resource/models/resource.py
+++ b/addons/resource/models/resource.py
@@ -474,7 +474,11 @@ class ResourceCalendar(models.Model):
         """ Wrapper on _schedule_hours: return the beginning/ending datetime of
         an hours scheduling. """
         res = self._schedule_hours(hours, day_dt, compute_leaves, resource_id, default_interval)
-        return res and res[0][0] or False
+        if res and hours < 0.0:
+            return res[0][0]
+        elif res:
+            return res[-1][1]
+        return False
 
     @api.multi
     def schedule_hours(self, hours, day_dt=None,
diff --git a/addons/resource/tests/test_resource.py b/addons/resource/tests/test_resource.py
index a01bc7ec63f..9fd6dddf8a8 100644
--- a/addons/resource/tests/test_resource.py
+++ b/addons/resource/tests/test_resource.py
@@ -273,6 +273,9 @@ class TestResource(TestResourceCommon):
             td += item[1] - item[0]
         self.assertEqual(seconds(td) / 3600.0, 40.0, 'resource_calendar: wrong hours scheduling')
 
+        res = self.calendar.schedule_hours_get_date(-40, day_dt=self.date1.replace(minute=0, second=0))
+        self.assertEqual(res, Datetime.from_string('2013-01-29 09:00:00'))
+
         # --------------------------------------------------
         # Test2: schedule hours forward
         # --------------------------------------------------
@@ -299,6 +302,9 @@ class TestResource(TestResourceCommon):
             td += item[1] - item[0]
         self.assertEqual(seconds(td) / 3600.0, 40.0, 'resource_calendar: wrong hours scheduling')
 
+        res = self.calendar.schedule_hours_get_date(40, day_dt=self.date1.replace(minute=0, second=0))
+        self.assertEqual(res, Datetime.from_string('2013-02-26 09:00:00'))
+
         res = self.calendar.schedule_hours(
             40, day_dt=self.date1.replace(minute=0, second=0),
             compute_leaves=True, resource_id=self.resource1_id
@@ -401,6 +407,11 @@ class TestResource(TestResourceCommon):
         # 7h30 -> 12h30 = 5 / 13h -> 14h = 1 / -> 6h
         self.assertEqual(res, 6, 'resource_calendar: wrong get_working_hours computation')
 
+    def test_45_calendar_hours_scheduling_minutes(self):
+        """ Testing minutes computation in calendar hours scheduling """
+        res = self.calendar.schedule_hours_get_date(-39, day_dt=self.date1.replace(minute=25, second=20))
+        self.assertEqual(res, Datetime.from_string('2013-01-29 10:25:20'))
+
     def test_50_calendar_schedule_days(self):
         """ Testing calendar days scheduling """