Fixed start and end dates of release phases Merged

We work in our program with firm defined scrum sprints of 2 weeks, i.e. each scrum sprint has a firm start and end date. 
When I add a feature to a sprint, the feature must inherit the start and end date of the scrum sprint (release phase) it is added to.

I have not found the way to do this in Aha.

What I have come up with so far is:

• Define a release template with the defined sprints (release phases) on product line level so that all Product Owners can use that for their product. Great feature! 
• When I then initially assign a feature to a sprint (release phase) the feature indeeds inherits the start and end date of the release phase. So far so good. 
• When I move the feature to another release phase then the start and end date of the release phase are changed based on the start and end date of the feature. That needs to be the other way around.

I would expect this functionality to be available in an Agile tool like Aha! As this 'Fixed start and end dates of release phases' is required to do scrum essential way of working. That is why I classify it as I need it yesterday.