Once a timesheet has been exported from Workforce.com, it will become locked for editing. The timesheet export permission level is required to unlock a timesheet which has been exported.

You will see the 'unlock all timesheets' option at the bottom of the page when viewing the timesheets for a prior period.

Once the changes are complete, timesheets can be locked again by selecting the Lock all approved timesheets option.

Timesheets can also be unlocked individually by opening the timesheet of a single employee, using this unlock button at the top of the timesheet.

Managers are able to do this for teams they manage. You can enable this by navigating to “All Settings”, “Advanced Settings” and then “customise access and roles”. From there you will find this menu:

And you can enable the permission here: