diff --git a/src/ifcopenshell-python/ifcopenshell/api/sequence/edit_task_time.py b/src/ifcopenshell-python/ifcopenshell/api/sequence/edit_task_time.py
index c4d38d2c4d..d11ed51036 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/sequence/edit_task_time.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/sequence/edit_task_time.py
@@ -12,6 +12,9 @@ class Usecase:
 
     def execute(self):
         # If the user specifies both an end date and a duration, the duration takes priority
+        if "ScheduleDuration" in self.settings["attributes"].keys():
+            if self.settings["task_time"].ScheduleFinish:
+                del self.settings["attributes"]["ScheduleFinish"]
         if "ActualDuration" in self.settings["attributes"].keys():
             del self.settings["attributes"]["ActualFinish"]