FLOW: Workflow for new Employee / Create Planner Task wie an "entered" due date

Hi everyboddy, 

I´m playing with FLOW for creating a workflow for "setup" new Employees, which means:

If I start the flow, I enter some important Data for the new empoyee (Name, Department, DATE of first workday) - and after this, the flow creates different tasks for different departments inhouse, so they can make their nessecery jobs (such as Order Notebook, setup AD-user, activate Mobile-SIM, and so on). 

My problem is: I would like to schedule this tasks according to the date when the employee starts to work (so calculate from due-date, NOT from now). Therefore I would like to set the DUE Date Time for a task in dependance from the entered start-date. 

For example: 

 

Employee start ad 01.03.2018. --> So due date time of the task for the notebook-order schould be 6 Weeks in front of this date. The due date time for the Task for creating AD-user schould be 1 week in front... and so on.

 

But: If have not found a possibility to set such a due date time dynamically according to an entered Date. It seems only be possible to have a "utcNow()" +- whatever. 

 

Any Ideas?

 

Thanks in Advance,

Ruediger