Moving actual when ahead of schedule

If you complete a task before it was planned to be finished. How do you drag the “Actual” back, pull the dependencies back and consequently show that you are ahead of schedule.
At the moment when I try to pull the actual back, all it changes is the constraint date “Start no earlier then”.

Thanks for your help

If you adjust the Actual Start/End in Inspectors > Task > Schedule, that should do the trick. If it’s still not working, then there may be other prerequisites to the task in question, that are preventing you from moving it earlier. In that case, View > Show Scheduling Influences can be very helpful!