How to change the default values for automated appointment reminders

From the PetalBooking interface: 

1. Settings section
2. Reminders tab
3. Make the necessary changes in the different subsections.
4. Edit
5. Save.

Subsections

Time reminders
Information that will be added to emails and SMS reminders.

Acceptable hours for sending reminders
Specify the times to send appointment reminders. If a reminder arrives outside of these hours, it will be sent as late as possible the day before or as soon as possible the next day.

Attachments
Add documents that will be attached to appointment reminders sent by email.