There are two types of Self-Book templates that allow visitors to your calendar to submit events: "Make a Reservation" and "Suggest an Event." Both of these templates let visitors choose the date and the time of the events they're submitting. 

If you want to restrict times of day and days of the week that your visitors can submit reservations or events, you can edit your Self-Book templates following these steps. First, you'll need to open the template you want to edit:

Once you have clicked on the checkbox next to "Enable Availability Scheduling" in the "Availability Schedule" tab, you can then choose when you want to limit submitted bookings to your calendar. Follow the steps in the image below:

You can click on the "Add Another Rule" button to choose separate sets of days and times you want to allow bookings. For example, if you want to allow bookings between 8am and 12pm 5 days a week, but you want to allow bookings from 2pm to 4pm only 4 days a week, you would add another rule to list this separate set of days and times. Be sure to save your changes.

By default, these rules will stay in place until you edit the Self-Book template again. If you only want to have limited booking dates and times for a specific period of time, you can click on the "Add a New Schedule" button to choose when these limited booking times will run. See the image below:

You can also choose what custom text you want to display when your visitors try to submit a reservation or suggest an event during a day or time that is blocked off under "Availability error text."

When you have availability scheduling turned on, any calendar that you've added your "Make a Reservation" or "Suggest an Event" to will show the available times to submit an event in white, and the unavailable times in gray. You'll need to be viewing your calendar in Day View or Week View with the Day Grid turned on to see blocked off times. To see blocked off days you can be in any calendar view. See the image below: