The Task Timeline Duration does not match the fly-out or on the grid.
STEPS TO REPRODUCE:
Expected Results: The Duration value in the Timeline Column cell should equal 20 days.
Actual Results: The Duration value shows 25 days.
This has also been seen where the duration is 1 day (not a milestone). Timeline shows 0 but grid and the flyout shows 1.
This is caused by DE61118
DE61118 is fixed in 15.9.3