Yes!
In BillDr any case you start can be viewed or finished by a team member. The BillDr dashboard can be sorted by "my orders" or "team orders". If you have started a bill sheet and need to leave the case be sure to return to the BillDr dashboard so any changes you made are saved. Then another team member can pick up where you left off.
In BookIt, every case that you add is automatically shared on your team calendar. You don't need to do anything special.