The timesheet period is set at the account level by an Administrator in Settings > Account settings > Schedule.
The available options for the timesheet period are:
Weekly (starting on a selected day of the week)
Bi-weekly (starting on a selected date)
Semi-monthly (1st–15th and 16th–end of month)
Monthly (1st–end of month)
The selected timesheet period will affect:
Displayed days in users' Track view when entering hours. For example, if the period is monthly, they will get an entire month in their Track view.
Timesheet submission. When a user manually submits their hours, the entire period gets submitted.
Timesheet validation. When submitting a timesheet, worked hours are checked against target hours for the timesheet period.
Weekly summary report emails. The summary email goes out the day after each timesheet period ends.
Over-target and under-target timesheet period reminders. The reminders go out the day after each timesheet period ends.
Period locking. You can set the period to lock for edits after a selected number of days after the timesheet period ends.
Working days
All of the above will also take into account the selected working days and daily target hours:
Non-working days will be marked with grey in users' Track view, and they can hide or display them on the timesheet by clicking on the eye icon:
If users enter time on non-working days, it will be counted in their worked hours and towards their target.
For setting up custom schedules for certain users, default working days and target hours can be overridden for individual users on their profile in the Users tab. The timesheet period, however, is the same for the entire account.