Appointments only for the day of? – Opensalon - Hair Salon Booking Review

The app seems to be ideal for booking an appointment and getting an adult (male) cut in a reasonable timeframe should not be difficult. But it appears that you can only book for the same day. It would be nice to be able to book a few days in advance to make sure you have a spot. Or am I missing that functionality?
Review by Mark Vehec on Opensalon - Hair Salon Booking.