Time Locks are a great way to prevent back-dated entries from being entered or edited. Once a timeframe is locked, no one can change or add their time entries or expenses.
You can exclude users and teams from a lock, which is helpful if you need someone to correct their hours after a month is locked.
Usually, all projects on a timesheet are locked. An option is to close only specific projects. For instance, if you invoiced the time for a particular project in August, do not allow more tracked time in that month on that project.
Users see a little tooltip for why a day is locked in their timesheet. The reason can be customized, overriding the default "This day is locked" message.
When time is locked, all rates and calculated turnover are frozen. Changing the rate for a user will not affect the turnover, rate, margin, or cost for locked time.
Only users with the Admin or Manager role can lock time. Find the "Lock Time" option in the gear icon to lock time. Use the yellow plus button to create a new lock or pick a day in the calendar.
Select the lock and choose "Unlock" to unlock a previously locked timeframe.