a bus shuttle due to work on the line. Light rail service through the tunnel ended at 9 p.m. until October 2, when it was extended to 10 p.m. on Sundays and midnight on other days to better align with BART's late night service. Rail replacement project Around 2014, with the tunnel nearing a century of continuous use, Muni began planning a major track replacement project in the tunnel. The project would include the replacement of all rails and ties in the tunnel with new rails directly fixed to concrete pads, the installation of two pairs of crossovers (one near West Portal, the other just east of Forest Hill), replacement of existing switches to the unused eastern portals, a structural refit in the area of the former Eureka Valley station, replacement of the overhead wires, and a number of other repairs and improvements. The work would lift speed restriction that limited trains to through the tunnel and would allow for the use use of two-car trains on the K/T lines. The construction contract was awarded on April 5, 2016. The project was originally planned to begin in late 2016, but suffered a series of delays. The start date was first pushed to April 2017, then in March 2017 it was pushed to mid-2017 to allow for "additional technical analysis" of the tunnel. In June 2017, the project was indefinitely delayed after the construction contract was terminated. Muni and the contractor could not agree on a new schedule and costs to minimize disruptions to riders; and the project duration increased from 460 days to 807 days and the cost to $48 million. The SFMTA released a Request for Qualifications in October 2017, and bidding opened for the $35.5 million project in November. Work began on June 25, 2018, and lasted until August 24. During the closure, Muni Metro trains were short turned at Castro station; the surface section of the K Ingleside was through-routed with the J Church, while the L Taraval and M Ocean View were replaced by buses. Systemwide delays during the summer of 2018 resulted from a combination of the tunnel shutdown and decreased qualified driver availability, which in turn was attributed to the rollout of LRV4s (requiring driver training), and contract issues. Refurbishment work was temporarily suspended after a signal technician was fatally crushed by a steel beam on August 10. The technician was an employee of