User is still able to book time to a project despite not having access to the cost structure

Symptoms
User is still able to book time to a project even after removing access to the cost structure.

Reason
A user assigned to a task can log time for the task, regardless of the billing office / cost structure access. This behaviour is by design.

Resolution
If the user should be prevented from booking time to the task,

- the resource assignment needs to be removed from the task.

or

- lock the task assignment

or

- set up time entry restrictions to restrict time entry to be within task/project planned dates