Once you have logged into your calendar and registered your hours you must submit the time sheet for approval. By clicking Confirmed until in Calendar, you will see an orange bar indicating that your time list has been submitted for approval. The Orange Line will span the period you have recorded the hours on.
When your calendar gets a green line, this indicates that your time sheet has been approved by the employer. As long as the calendar consists of only an orange bar, you can still make changes, but when you get a green line, you can no longer edit the calendar.