Right now, if you click "Timesheet" in the navigation menu, you will enter your current timesheet by default, but it is not obvious where the rest of the previous timesheets live.
"Back to Timesheets" is not obvious, and the extra step doesn't make a lot of sense if you are a timesheet approver or plan on submitting last week's timesheet on Monday.
Please revamp the interface for the Timesheet area to be more navigable and user friendly.