No, with your combination ticket you do not have to visit all the attractions in one day.
Once you have made your booking, your email confirmation will include a link to pre-book the other attractions - You will be required to enter your Order Number and Email address used when booking to log in to the Booking Portal. You have up to 90 days from your first attraction visit date to visit the remaining attractions.
You have a maximum of 5 opportunities to edit your other attractions visit dates prior to the original date selected. Please note you are unable to amend the date and time of your first attraction visit.