In this latest update scheduled for release 14.12.15, we have improved the Claimed/Pre-Booking functionality.
If booking is allocated to you, you will see the booking on main screen 10 min before pick up.
You can then choose to start the booking instead of sitting around waiting until the booking get's dispatched.
In pre booking list, you will see jobs that you have claimed or those that are allocated to you:
10 minutes before pick up, your main screen will show a "Accept Trip" button. If you press this button the job will dispatch to you.