The proxy task is calculating as the wrong number of days which is incorrect based on the start and finish dates.
Steps to Reproduce:
1. Create a project, Project A with a total duration of 2 days (4/12-4/13)
2. Create a second project, Project B
3. Add Project A as a subproject of Project B
4. On the master project, Project B, go to the Task list or PPM Gantt and verify that the proxy task created for the subproject has a duration of 2 days
5. Go to the properties of the subproject, Project A, and extend the finish date to 4/20 (the total duration is now 7 days)
6. Go to the task list page or the PPM gantt for the master project, Project B
Expected Results: The duration for the subproject proxy task should now be 7 days.
Actual Results: The duration for the subproject proxy task remains at the old duration of 2 days. - The dates however have correctly updated to show 4/13-4/20.
DE40407 has been fixed on our 15.4.1 release.
The workaround on affected versions is to remove the subproject from the master project and re- add it. This will force the proxy task duration to recalculate.