Moving subtask does not move the previous tasks

I have a serious of tasks with depencies between them. Typical water fall
I i change a subtask down the stream - later - the prevous tasks does not follow.
I need to follow when to start on previous tatsks if a subtask is changed. - Later or earlier.

I am not sure that I completely understand what is the issue, but if you meant backward scheduling then it is not supported, sorry, although it is possible to emulate it with a little but clumsy technique:

this is what it is called - yes backward schedulling.

Ok i see.