A method of operating a laboratory sample distribution system is presented. The system comprises sample container carriers comprising a magnetically active device and configured to carry a sample container, interconnected transport plane modules configured to support carriers, and electro-magnetic actuators arranged in rows and columns below each transport plane module and configured to move a carrier on top of the transport plane modules by applying a magnetic force to the carrier. The method comprises assigning transport plane modules to a route category. At least two traffic lanes are formed on the route categorized transport plane module. The carriers are moved within each traffic lane in a transport direction. The transport directions are opposite to each other. The method also comprises assigning another transport plane module to a waypoint category. A change from one transport direction to the opposite transport direction is possible on the waypoint categorized transport plane module.