How do I remove the time base in Appointments + plugin?

Hello. First of all, sorry for my bad english.

I am creating a course purchasing website where you can book for a course and pay online so I decided to use this plugin as it has most of the features I need. But one problem is that a course can have up to 18hrs session and will be divided into several days (e.g. 18 hrs for the duration of 3 days). What I would like to have is to remove the time base selection so that users will just book for a specific day to start in the calendar and it's up to us to manage the schedule for the duration.

Hoping for your kind response. Thanks