How can I make a project billable but prevent employees from logging time to it?

In BQE CORE, you can prevent time entry on a project while still allowing it to be billed by applying the project rule, Prevent time entry for the project. This rule is set at the project level under Projects > Settings > Assignments. When this rule is applied, employees cannot log time to the project (and its phases, if applied there), but the project can still be billed using existing WIP or transactions from related phases.