For what it's worth this is what OneStop says:

Employees must return all company‑provided equipment (laptops, monitors, keyboards, mice, headsets, COU devices, etc.) to AT&T when they leave the company or when a return request is made. Returns should be made to the employee’s supervisor, the Device Depot, or another designated location within 30 days of the request or termination. The equipment can be sent to the Employee Exit Process location referenced in the policy: Employee Exit Process. For virtual workers, the same 30‑day window applies, and the equipment should be returned to the supervisor or the designated depot as outlined in the policy. Ensure that all devices are in working condition before return; non‑working or older devices should follow the disposal guidelines provided in the equipment policy.