updating sub tasks dates according to summery task

[amithrt]

Hey guys

i would like to know how can i set a relative sub tasks that their durations are known but i want the summery task to determine the actual dates.

For eample, if i set a project from jan 14 to april 14 and i was told to pospone it by month, so changing the summery task start date would shift it sub tasks.

I know i can create a "fictive" task and link it to the sub tasks but is there a better soultion?


Thanks