In some markets where a local cable provider carried Superstation WGN upon the initial rollout of the service, a WB 100+ affiliate supplanted WGN as the local WB affiliate; though for a year following the launch of The WB 100+, programming duplication between the local WB 100+ affiliate and WGN persisted in some areas where a cable provider did not black out WB programming airing over the WGN superstation feed. As additional WB 100+ affiliates signed on, network management deemed that The WB's affiliate footprint was large enough to request that WGN drop its programming from the station's national feed in October 1999; the local WGN-TV Chicago signal remained a WB affiliate until the network's September 2006 shutdown (the WGN local feed – which later became a CW affiliate, and is now an independent station – would become available to U.S. viewers outside of the Chicago market in the spring of 2015, when it was added as part of the initial offerings of Channel Master's LinearTV service).