To create a block viewing on a property during the property onboarding process go to Edit Property > Viewing Preferences > Block Booking.

You can then create multiple block booking slots on different dates, against a property and assign the relevant agent to the block booking, clicking save & continue located at the bottom right of the page.

There is a feature to the right of the screen which will remind you of the agents hours if accompanied to avoid clashes in the diary or working hours.

Once you have created the block booking slot, you can then see the block booking slot from the 'Create Viewing' screen. The block booking slot is also visible from the diary as seen below as well as visible at the top of the property page as an additional reminder.

You can then select a time that fits inside the block booking slot.