Rally: Task To Do hours not editable and the hours disappeared

Products

• Rally SaaS

Issue/Introduction

User is unable to edit To Do hours, the input is grayed out and the hours that were in there have been removed.

Environment

Component : AGILE CENTRAL

Resolution

When the State is updated to Completed, the To Do hours are removed and the field is no longer editable.

Why?  Because it is complete, there is no more to do on this task.   
If you do have more work to do on the task, please consider moving the State back to In-Progress until all work on the task has been completed.