"Available from" and "Due date" of Online text assignment is not linked to course start date

Overview/background:
As a course developer, I have created an online text assignment for use in a course. That online text assignment has a specific date range that does not appears to be linked to the course start date.
It is possible to recreate this problem by creating an online text assignment within a course. Then change the start date, as any institution might do when that institution offers the same course in another semester or academic year.

What was expected:
It was expected that the online text assignment would update the "Available from" and "Due date" fields based on the course start dates.

What actually happens:
When the course was actually run several months after its creation, the participants complained of past due assignment notices when they logged in. All such notices related to the online text assignment dates.

Suggested solution: link the online text "available from" and "due date" fields to the course start date, so that the online text assignment dates will automatically update when a new instance of the course is created.