Account admins can edit the workweek of all users in the account. For admins on Enterprise accounts, this right can be revoked.
If the workweek in your company differs from the traditional 5-day workweek, you can change it in the Work Schedules section of Account Management.
When you change the default workweek, it affects all users in the account.
On Business and Enterprise accounts, you can create custom work schedules. In that case, different users can have different workweeks.
Changing the workweek settings might affect some projects' and tasks' dates due to auto-rescheduling.