How Can I Change Hour Limitations for Same Day Appointments?

You can allow Customers to book same day appointments through the Customer View and require a specific number of hours prior to the appointment.
GO TO: Settings tab > Appointments > Preference #5 (Allow same day appointments)
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If you set this preference to allow same day appointments, you can still set specific hours limitations. For example, if you allow same day appointments but want to make sure that any appointments booked by customers still require at least 4 hours notice, this can be done for each schedule in your account. Once you set Appointment preference #5 to allow same day appointments, a new field will be enabled in the profile for each Staff Member.

This new field is called "Same Day Appt Notice."
GO TO: Staff Members tab > Select the Staff Member > Set hours in Profile Information
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You can set this by hours for each separate staff member.
​NOTE: Same day appointment notice only pertains to Customers booking appointments through the Customer View.