abandoned and replaced with the Phelan Loop at Phelan Avenue near City College. Service past the loop to Mission ended on October 10, 1952, although trackage as far as San Jose Avenue was kept for non-revenue moves to the carhouse. Service was diverted to Duboce Avenue, Church Street, and 17th Street on December 2, 1972, due to construction of the Market Street subway. On April 23, 1979, the line was lengthened to Balboa Park BART Station. Initially, only supplemental trips running from West Portal and using newly-in-service Boeing Light Rail Vehicles (LRVs) served the new extension, weekdays only, and most K-line service continued to use PCC streetcars running from downtown to Phelan Loop. The LRV shuttle service ended in February 1980, and PCC-operated service was extended to Balboa Park but lasted only four months before the weekday service was replaced by a temporary K-L crosstown route using LRVs (and weekend service cut back to Phelan Loop). Additional changes to the service configuration followed until finally on December 17, 1980, the K line became operated as a through service from Embarcadero Station to Balboa Park, using LRVs, on weekdays only. Weekend service continued to use PCC cars until September 1982, when the Muni Metro became fully operational. From February 2001 to June 7, 2003, K Ingleside service was cut back to St. Francis Circle and replaced by buses on Ocean Avenue for the Ocean Avenue Reconstruction and Improvement Project, a major street repaving and utility replacement project. The Muni tracks and overhead power system were replaced, boarding islands were reconstructed, and accessible platforms built at Ocean and Lee. Following service changes on June 30, 2007, the K Ingleside and the T Third Street lines were spliced together inside the Market Street subway tunnel, though keeping their respective line designations, resulting in an upside-down horseshoe-shaped route from Balboa Park to Bayshore and Sunnydale. At West Portal Station, inbound K trains heading towards downtown change their signs to the T line; conversely, at Embarcadero Station, T trains heading into downtown change signs to the K line. The trains show the ultimate destination of the spliced lines rather than the intermediate "terminus" of the individual line. Later changes Service on the line was modified from June 25 to August 24, 2018 due to the Twin Peaks Tunnel shutdown. The underground section of the line was closed west of Castro station, while the surface section