Hi,
You can customize both Schedule board & Schedule assistant.
For schedule assistant, please follow the steps below.
1) Go to Resource Scheduling - Administrator
2) Select 'Enable resource scheduling for entities'
3) Now 'Setup Wizard - Enable scheduling' page will be displayed,
4) Open the required Entity to open the 'Booking Setup Metadata' form
5) Use the 'Schedule Board Setting' link on the ribbon to start updating the Filter Control.
Have fun :)
Regards,
Faiz