Let suppose i have a sprint which is of a week and I start with my sprint today at 20th Dec and define the due date to 26th Dec.
1. What happened is the Tasks defined in sprint were decided to be pushed into the next sprint cycle. So 2 consecutive sprints are already defined in redmine
2. On completion of sprint cycle when the sprint status is changed to closed, the PBI item with open Tasks may automatically be moved in next sprint cycle.
If we can have a automatic date picker then the problem to automate the task can then be easily done by just closing the current sprint.