Why Is My Activity Open Duration Date Limited?

This article provides an explanation to why open duration periods are limited in InteDashboard when creating your activities. 

The time on InteDashboard works based on permissions in relation to open periods. So if your regular overall course is set to be open from June 2020 to December 2020, then your modules will only be able to be set under that period.

You can always change your open dates for your main course in the Manage Course area, but then you'll have to create (or duplicate and edit) new module and activity dates so the new time permissions can be utilized.