Let's say you have a weekly recurring task. If you are using time estimates as part of your workflow you would want that task to always have the same time estimate and perhaps a frog or star. Or you might want to add subtasks or a note that always shows up with this recurring task.

It's important that you add any attribute to the parent task so every instance of the recurring task has it and not just an instance of the task in your day. 

Each recurring task in your day is independent of the others, so if you just edit a recurring task in your day view, the change only applies to that specific task.

To edit a parent task, find the recurring task either in the Master List or in the recurring tasks overlay (accessible through the menu on the top right) and click on the edit icon (pencil) to open the recurring task dialog.

To add an attribute (star, frog, time estimate, label) to the recurring task use the task input shortcuts.

Example:
To add a time estimate, click on the title and add the estimate with the "~" symbol like above. After pressing enter the attribute gets added.

To add a note or subtasks, hover over the task and click the button on the right:
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Depending on the attribute you can remove it like this: