Apparatus and devices for percutaneously extending an existing spinal construct ipsilaterally with an additional spinal construct in a patient are disclosed. The cap is characterized in that it has a closure plane, a circumferential outer skirt for engaging a container, and a circumferential resilient depending inner member. Specifically, a dynamic bandwidth allocation algorithm operates from limits calculated based upon available ports per subscriber, expected user bandwidth, and parallel user bandwidth versus throughput. Actuators can pivot the bars from their rest positions into their working positions.